And why 3DS is so "much better" product that sold so much better? Biggest difference are ofcourse huge system seller games and full Nintendo support. In world of phone/tablet gaming you need to have huge and great games in order that people choose dedicated handheld gaming console instead phone/tablet.

There are several differences between Sony's handhelds and the Switch.

First off the PSP launched at $250 with a $20 memory stick needed to play most games. That was back when the DS launched at $150 with no memory stick needed. Adjusted for inflation the cost of a PSP and memory stick in 2005 was $330. That's even more expensive than the Switch, with a direct competitor for $120 less.

Neither PSP or Vita could play games at home on a big screen T.V. without already owning another console.

Vita doesn't have a library of exclusives. It was just a port machine all the way through. The only good Vita game that wasn't playable on another system was Ys: Memories of Celceta.

Finally, the PSP and Vita weren't console quality. Maybe the PSP was if you stack it up against PS2. But the Vita definitely wasn't.

Man...what the hell is up with threads today? They're either very odd questions with obvious answers or weird comparisons with huge leaps in logic.

The Vita didn't fail because it had console games on a portable. It failed because it was expensive, it had propriotary memory, and because Sony didn't support it past like two games.

The 3DS most importantly... and perhaps most ironically... had games that made even home console gamers want to buy it. The most beloved Zelda remasters were exclusive to 3DS, so was one of the best strategy franchises ever, as well as JRPGs like Bravely Default.

The Vita was $250 and the Switch is $300. The memory card wasn't mandatroy for the Vita. Most games just saved to the system memory or the internet. 

But yeah, Sony didn't take any chances with exclusives on the Vita. Every single good Vita game with the exceptions of Ys, Tearaway, and Gravity Rush was a port. But Sony didn't keep two of those as exclusives, and sent them to PS4. Imagine in the 3DS had no original exclusive titles. It would have sold like crap too. 

Sony shit the bed with proprietary memory card prices.

While that is true, the Switch doubles down as a home console. It really isn't the same especially when you consider software sells hardware. If you really don't think the propriatary memory had a big effect on Vita then idk what to tell you man. It stopped me from getting one. 

But this is a different beast, this is an hybrid, is not perceived fully as a handheld or a homeconsole, it is portable, and portable games fit really well there, but also has a very big screen and is very powerful, so it gives a very convincent homeconsole experience on the go, way better than any other console before. People didn't bought NDS to play homeconsole games on the go, because it wasn't the right machine for that, so Nintendo, who really understands this market, made games that fit the the console, Switch however is a great machine for both kind of games.

Just play along.

I am quite sure if games like uncharted, the last of us and god of war from ps3 all had 1 on 1 releases on vita it would have been a much higher selling console.

Nintendo is all-aboard the switch when it comes to support and that is something Sony never managed to do, sure it had some good exclusives but the best exclusives where always just on their home consoles.

Vita simply lacked a good library of games. If it had gotten the same first party support Nintendo gave the 3DS it would have sold better.

Switch sells because it keeps getting good game after good game. This year we'll still get Steamworld Dig 2, Pokkén Tournament, Super Mario Odyssey, Doom, Xenoblade Chronicles 2, Skyrim: Special Edition, Fifa 18, Axiom Verge, Battle Chasers: Nightwar, Thimbleweed Park, Rime, L.A. Noire, Resident Evil Revelations 1 & 2, Wulverblade, Golf Story, Rocket League, etc.

Switch has everything: big, small and medium-sized games. 

In its first year on the market the Vita had 16 games that scored over 80% on metacritic. The Switch currently already has 21 and there's still 3.5 months to go.