Googling is hard. Let me help you.
http://lmgtfy.com/?q=psvr+upscale+framerate
http://lmgtfy.com/?q=ps+vr+asynchronous+time+warp
If your sticking point is the terminology, call it whatever you want other than upscaling, that's just the term the press has been using, but the result is the same.
As for PSVR games looking like PS2 games, while some may look like that and be easy to run, there are many others that won't be natively
run at more than 30fps. Look at games like Adrift, Ark: Survival Evolved, Eve: Valkyrie, etc, all among the games listed for PSVR, and games which the PS4 will never come close to being able to display at an acceptable framerate for VR.