A 2020 launch makes sense in terms of allowing PS4 to have the spotlight as long as it can, but it also allows XB to potentially compete side by side once again like in 2013. Assuming XB has learned their lesson and has a much stronger launch than XB1, PS may very well want to get a head start with PS5.
Now if PS launches PS5 late 2019, they may lose some PS4 sales because of this, but may also just transfer some of those potential sales to PS5. This would lead me to believe that PS may give PS4 the 2019 holiday, and then announce PS5 early in 2020, say February, with a launch somewhere between then and E3. I would have to assume a late 2019 or early 2020 launch would mean a $450 or $500 price, with it dropping to $400 by holiday 2020 if necessary, to be competitive with the 'XB2' specs or price, if it launches then.
I really think PS should drop Pro and sell a Pro II (PS4k) and end up slightly above XB1X specs. Whether PS just uses the Pro hardware now and shrinks it from 16nm to 12nm but increases the clocks to do it, or uses newer compatible hardware, as long as the price can be $400 to $500, it should sell well enough. It would also give them some indication of how a PS console would sell at a higher price point than $400. Better to find out if it's not going to work now while PS4 is doing so well, then to find out at the PS5 launch.
Another PS4 upgrade soon, would allow PS to sit back and see what XB does. If they decide to launch 'XB2' late 2020, PS should be able to announce PS5 before 'XB2' launches and let gamers know they only have to wait 3 to 6 months for PS5, and that should work out fine for them. Having to wait an entire year would be more risky. If XB waited the full 4 years and went with a late 2021 launch, which would be the latest they would wait, PS could have PS5 ready to launch early 2021 regardless, and if they decide to get it out before "XB2' then great, and if not, just keep quiet and launch it late 2021 as well.
If PS5 were to really launch late 2018, I could only guess that PS has planned on a 5 year gen with no upgrades. There is so much new tech that is here now, just slightly too expensive still, that dragging PS5 and PS5 Pro out from 2018 to 2024, would seem like a misstep to me.
PS1 - ! - We must build a console that can alert our enemies.
PS2 - @- We must build a console that offers online living room gaming.
PS3 - #- We must build a console that’s powerful, social, costs and does everything.
PS4 - $- We must build a console that’s affordable, charges for services, and pumps out exclusives.
PRO -%-We must build a console that's VR ready, checkerboard upscales, and sells but a fraction of the money printer.
PS5 - ^ -We must build a console that’s a generational cross product, with RT lighting, and price hiking.
PRO -&- We must build a console that Super Res upscales and continues the cost increases.
