Some people will no longer need a high-end GPU for gaming, sure. This looks like a great way to play games for people with fast enough internet speeds. But for the rest of us, it won't really be a good option for a long time. I'm sitting here in Germany with a 50 Mbit/s connection that rarely ever reaches that maximum and hovers more around 20-30 Mbit/s most of the time; and 50 Mbit/s is the very maximum that a lot of private households in cities have here.
These 20-30 Mbit/s is a speed where I can just (barely) stream a 4k30FPS YouTube or Netflix video without any stuttering if nobody else is doing any significant downloads/streaming on the same network, and that's with their relatively high compression algorithms. Video games generally require much higher bitrates in order to look great, and that's without even talking about 60FPS (or even higher framerates), HDR, VR headsets (that run many games at 120FPS standard), or as
@NBAasDOGG pointed out, input lag which may make a lot of games that require quick reactions unplayable/unenjoyable. I once tried the PS4's Shareplay feature with a friend, it was not a great experience.
And many households on the countryside here in Germany are still stuck with 16 MBit/s connections. Good luck even playing anything above 1080p with this.
And that's without even talking about what this means for modding communities, or for developers who, for one reason or another, either cannot or don't want to bring their games to such a streaming service...
Don't get me wrong. A lot of the things in the video look really promising. Being able to immediately jump into games without waiting for hours or days to install them, being able to seamlessly switch between devices Handoff-style, playing games even on mobile devices or on computers without a strong enough GPU... sure, sounds great. But for a lot of us, it will be many years before we'll have the internet speeds for this to replace conventional PC/console gaming.