Dude literally no one wants that except for you. There's a reason both Xperia play and the 3g Vita were massive duds and doubling down on that idea would just cause further losses. Hell why is this even relevant here this thread is about 3rd party support

Bad sales, bad support. Not a coincidence. Also it wasnt quite powerful enough to handle ports with ease so it got pushed aside.

3DS saw a decline in support as well. Not just because of lower sales than DS but many developers began focusing on Android and Apple mobile games.

Tegra X1 and X2 are ancient tech at this point. Ryzen/Navi on 7nm will run circles around those chips. Battery tech is making serious leaps at the moment, which will make things even more viable in the next year or two. We basically have the perfect mix of tech to make this happen. Really, 7nm+ Ryzen/Navi + a Solid State Battery should offer an amazing Mobile Console Gaming expereince.

The reason 3rd parties didn't support Vita, is because Sony dropped Vita in favor of Xperia. Vita didn't fail simply because it wasn't a good platform. Sony killed Vita, they didn't want 3rd party support. 

Xperia Play and the 3G Vita didn't fail because people don't want gaming phones/connected portable gaming devices. They failed because people don't want unsupported platforms.

Xperia Play had no 1st or 3rd party titles, no Online Multiplayer, No Friends List, nothing. It didn't even ship with access to the PlayStation Mobile store. You had to turn off the safe apps feature in android, find the hidden PlayStation Mobile site, and download/install it yourself. On top of all of that, it was had terrible hardware specs compaired to other phones at the time. 

The 3G Vita's had multiple problems, but its biggest was Sony killing it off to focus on Xperia. On top of that though, the exclusive AT&T did it no favors at the time in the US. It lacked Online MP. It was and still is limited to 20MB downloads. Sony never even marketed the Skype feature. 3G Vita in its execution is no indication of people not wanting a connected Portable Gaming device. 3G Vita is an example of poor use of good technology, and absolutely no marketing.

Wrapping things up in connection with 3rd partyy support, I bring up the possability of a future PlayStation Portable that would have 100% 3rd party support thanks to a unified architecture with PS5. A connected version could be made as well, a 5G PlayStation Phone would be able to deliver an uncompromised online gaming expereince. 

The idea that no one wants a connected Portable gaming device, with a full lineup of current AAA 1st and 3rd party titles is complete nonsense. Switch is living proof of this at a small scale. A device that gets full 3rd party support and connectivity outside the home will only perform even more impressively. No one can convince me for a second that a connected Portable with Fifa, Madden, NBA 2K, Red Dead Redemption 2, Call of Duty Black Ops 4, Fortnite, PUBG, God of War, and Spider-Man would not be selling successfully right now.

This is not true.

The reason the Vita had terrible third party support was despite its comparatively great developer tools, and Sony's  unprecedented support of the platform (giving away developer kits, offering to send members of their team to assist in solving technical issues of bringing games to that platform) it was just very, very difficult to port a PS3/X360 game to the Vita. It required essentially remaking most of a game from scratch. It required massive, massive downgrades, and a disturbing amount of effort

... for crap sales on a platform that was too expensive and not powerful enough to offer the experience its userbase wanted to get from it. People wanted a handheld console they could play PS3 and Xbox 360 games on. They wanted Assassin's Creed, Borderlands 2, Madden, Uncharted, Fifa, Call of Duty, etc. on the go offering a user experience that was nearly as good as the PS3/X360. The Vita came well short of that. The big titles that were "ported" were poor substitutes for the home console experience. It has nothing to do with Sony's support and everything to do with them releasing a console that just couldn't perform the way they expected it to. The Vita's release was a still birth it just took a year for developers (and Sony themselves) to realize it was more effort than expected, and it just wasn't worth the effort.

So, we actually agree on something. Sony killed the Vita in favor of Xperia. They made a choice at the time based on a number of reasons to abandon Vita. SCEI initially was all in on the Vita there is no argument there, but at some point Sony Corp cut the cord. After that they had no interest in 3rd party support.

In ways it makes sense, Xperia was selling 50M units a year at that point, it is not impossible to see how executives at Sony Corp favored Xperia. I knew it would not work, but that is because I understand Sony's customer base better than they did. Sony has always failed when they try to ride on others success. Sony only succeeds on their own expereinces. No one wants Windows and Android devices from Sony, people want Sony devices, and Sony expereinces when they buy Sony.

Executives now, have to be looking at Xperia selling less than 10M a year, and loosing $1 Billion per year, and realize they made the wrong choice. Had they dumped $6 Billion into Vita over the last 6 years, it would have been massively more favorable for them. Going forward they need to take lessons from this. 

I completely agree with the Vita's short comings you mentioned. Having Vita and PS3/PS4 built on seperate architectures with the scope of games at the time just didn't work. It was an old business model, and it just doesn't work anymore. Even Nintendo has had to leave that model behind. That is why I continue to say, going forward, Sony needs to unify their ecosystem around AMD CPU/GPU tech. They need to be able to build one game that scales for 720p-1080p Mobiles to 4K-8K Home devices. The days of building a game twice for different architectures are over. 

That is the only way they compete going forward as the gaming market opens up. That is the only way they can fully support 1st and 3rd party gaming across every product in their lineup. AMD based PlayStation Portable, AMD based PlayStation Phone, AMD Based PS5, AMD based PS5 Pro, AMD Based Bravia TVs, AMD based PlayStation Cloud. They build one game, and it scales between 720p/30 - 8K/30 depending on the platform it is being played on. 

That is the future of gaming. Sony can either be a leader, or everyone else will do it and pass them up. Then they will loose 3rd party support on PlayStation all together.

They failed with the hardware design.
It was too expensive, and over designed for its time. With needless features that drove up prices, and those memory cards that cost a arm and a leg.

The hardware killed any future the thing had sadly.
If they had made a cut back version, without many of those near useless features, and useing normal memory cards, that sold cheaper, the vita would have been a much better selling product, and would then have had much more software support.

No. Sony didn't kill the Vita in favor of xperia. Not even a little bit. Sony didn't kill the vita. it was still born. They thought they were making something that was much easier to develop for than it turned out to be. It was never going to succeed. They just saw that developers weren't going to put the time necessary to make a port that was so substandard compared to their X360/PS3 counterparts that would never sell well. So they let the sinking ship sink, and instead focused their efforts into the PS4 and PSVR (not xperia). It had little to nothing to do with the difference in architectures. If for some reason the vita used a x86-based processor, it wouldn't have suddenly made it much easier to develop for. That isn't how this shit works no matter how much you insist it to be so. Console games do not scale that way for very obvious reasons that you continue to ignore.

Also, Sony's playstation "lineup" is a lineup of one device and one sub device, that is the PS4 and PSVR. That's it. Add to it a PS5 in the next couple years that will probably be X86/AMD based, and that's Sony's "lineup" for the next 5-6 years.  There probably isn't going to be another PSP (and if it does come in the next couple years it won't be playing PS5 games natively), and there definitely, definitely isn't going to be another playstation phone, or tvs that share common architecture for literally no good reason. I've already detailed many times how ludicrous it is for Sony to try to introduce a new operating system into the Smartphone market, much less the television market, but you continue to ignore that as well.

But let's be very very clear about something. You do not understand Sony's userbase better than they do. Full stop. You don't. Don't even pretend you do. I can't even imagine the arrogance someone has to possess to even think that they know better than a multi-billion dollar multi-national corporation about their own markets when that someone literally has zero credentials or anything else that would lend them any credibility on the matter. Do yourself a favor, demonstrate with tangible results that your ideas for how to move the gaming industry forward are the most profitable. Turn your ideas into an extremely lucrative career as the people who apparently you know better than have done. It shouldn't be any trouble for someone that apparently knows the gaming industry better than Sony does.

Sony is on the verge of having the three best selling home consoles of all time, and four of the best five in four tries and you think you know their userbase better than they do. Unbelievable.

Side note: AMD-based cloud? Do you have a slightest idea of how cloud networks work? What are you even getting on with now? You're getting further and further and further from reality as time passes.

Wasn't that just a PS1 peripheral? I'm not even sure if it ever released in the US. I wanted one but never saw one in the wild.