A PSP follow-up would actually be good for Nintendo. It would mean more AAA titles that could be ported to Switch as optimizations between two handhelds would be less of a gap than from current home consoles.

The opposite of this is true. The Switch is already catching steam as far as portable titles go, and they could be ported to the PSP3, which is yet to prove itself - after all, much less money is needed to make a port than develop something completely new. 

We're closer to 2 years from that being a possible reality unless you're talking a device that costs $500-$600+ and even then there would still be issues, and Nintendo would be able to match that themselves with a new model Switch thanks to Nvidia and have new Nintendo games (all of them), whereas the Sony product would just have secondary Sony support at best. 

Don't see if being worth it for Sony, especially since they are basically right now going to have to start focusing on Playstation 5, which will require monstrous resources. The current equilbrium right now works well for Sony, Nintendo stays in the hybrid/portable lane, brings in younger gamers to the hobby, and that leaves the Playstation brand with the traditional home market and only Microsoft to really worry about. 

If PS5 is a 2019 product, game development basically has to be starting like right now, you need at least 2 years to get games ready, probably more. Even 2020, you have to start development in the next few months. And PS4 will still have to be supported for several more years. 

If there is one it will be a PS4 Pro but Slim.

Is it that you think releasing new hardware= better sales or is what anyone wants?

As you said the pro released in november last year. Its still being outsold 5-1 by the cheaper PS4 that was released 4 years ago.

Again as you said.... games is are all that really matters at this point. This far into the gen everyone kinda knows what to expect from these consoles.... refreshes or not.

If they do just be a special edition of PS4 for a game bundle. Like maybe a God of War special PS4.

Most probably a Slimmer version of PS4 and PS4Pro; and maybe PS4Portable :)

Yes but if power is what you want, the PS5 won't be for you.

Nope there probably won't be any new hardware announcement until at least 2019. Sony has absolutely no reason to fear the Xbox One X at the moment sure they can't say they have the strongest hardware anymore but they are still the market leader by a good margin. They still got the most third party support and have more diverse exclusives then Microsoft and got the marketing to the most important AAA third party games.

You think the PS5 is gonna be Sony's answer to the Switch? 

Probably not a Pro slim this year (because too soon for 7nm APU), but a less power hungry Pro would be nice. Like when they released the PS4 1200 with newer models of grdd5 chips.