There are rumors/leaks recently that are showing that Ryzen 4000 mobile APU's will be capable of PS4 levels of performance at just 15w. That's with 8 Ryzen CPU cores on 7nm next year.
If this is true, then Nvidia should be able to create a similar performing SOC soon that can do so under 10w with their tech.
The big question is how much would that cost next year? It should be reasonably doable all around by 2021 though. Definitely by 2022. By then we will be a year or two into a new gen with consoles around or above 10TF, so a 2TF handheld (while docked anyway), wouldn't be out of the question.
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.
