I don't know who's actually using these kinds of game streaming solutions, or what games they're playing with them. The PSN version of the idea is basically unusable for FPS games, and I have a good broadband connection. Even Steam, over the LAN, Steam introduces a noticeable-enough lag that I just don't bother. But things like Stadia make it seem like enough people are getting mileage out of these solutions to make it profitable to run, so I guess I'm not the target demo.
There are enough people that just aren't that sensitive to latency. For reference, look at any console player that doesn't go out of their way to enable PC/game mode on their TVs (HDMI 2.1 with Automatic Low Latency Mode is thankfully changing this) that is going to suffer upwards of 100ms of input latency[1]!
I haven't tried the cloudygamer options recently, but I had no problem playing Destiny and The Division 2 multiplayer on Stadia. PSN might just be unoptimized.
