Wasn't aware of the YT thing.
There is a very large segment of the gaming community that's all about the 120-144hz experience these days. A lot of that is how it feels. At "just" 120hz that's only 8.33 frame time. You start throwing in 20ms of input latency on top of all the rest and you'll never get that 120hz experience.
It doubly won't cut it for the PC VR crowd. Ever.
That's high-end low latency experience but where things are headed and certainly noticable by non-pro gamers. But sure, it's high-end.. Even though the PS5 supports 120hz.
But forgetting high end, 20ms is more than a frames time at 60hz! PC Gamer's review of Stadia had the input lag as high as like 70ms on some titles doubling the total input latency!
For example, I wouldn't use it to play CS, LoL, DotA or any other competitive game where reflexes matter.
However, these services are great for AAA single player games, like Witcher 3, Cyberpunk, RDR, The Last of Us etc. You can max out the graphics and enjoy the story/game world.
I haven't seen any bugs in the past few months. You can also join games from Youtube now (launched like 3 or so weeks ago).
Google has never abandoned paid services, only free ones. Although they do migrate them sometimes like with Play to Youtube Music.
The repurchasing of games is valid criticism. I know they are currently working on adding support for Ubisoft+ games, which I believe will be live 2021 Q1 based off language in their updates.