Geez. Why is everyone so vicious? I mean it's free. It seems like no one had ever tried it, but everyone is so elitist they will stomp all over it.
It might be free from Google, but with how its eternal 1080p resolution (4K is a nasty, nasty lie, as has been proven repeatedly) eats through peoples' data caps...the ISPs won't be as generous.
Everybody is always vicious. Gaming companies need to earn their money -- dance monkey dance and all that.
Some also dislike what they perceive it to be (a means of preventing people owning games, though I find it particularly amusing that they will run off and cuddle up to Steam as though it has done no wrong but hey). In this case it was something of a rental service wherein one did not own the games you got to rebuy on it (for considerable sums no less).
The performance of it was less than stellar and anybody that knew physics* knew it would be, quite why google's famously on form engineering department did not know I don't quite know but oh well. Though actually it was not even physics peeps but those that had seen them all before.
*Grace Hopper's version being my favourite example
Though it does also follow that sticking it in a cabinet or an exchange in a city likely will be fine for most purposes. That is an expensive hobby, if one some companies already do (netflix and other streaming services have been seen to do this to avoid backbone bandwidth fees), so seemingly not done in this instance.
Except that, unlike Stadia's vegetative corpse, Steam actually allows players to download their purchased game files, and has promised (yes, publisher promises are worth less than dog shit, or alternatively modern Pokemon games, but still) that in the event Steam closes down Valve will let its customers keep said game files. As long as said customers actually have a HDD or several large enough to hold all of them, anyway.
If Stadia collapses - which is almost certain, due to not only its shit reputation and Google being known for killing off unrewarding ventures - then its customers won't be able to keep their game files, only their "metadata" (which, from what I remember, was never exactly elaborated upon, but was taken to mean save data).
Oh, and a "rental service"? Yeah, no, things cost way too much to be a digital version of Blockbuster or Netflix's infancy, or Video-EZY (if you're Australian). Back in "the good ol' days", rentals used to cost a fraction of the purchase price. They did NOT cost the same as the purchase price, let alone higher. That "rental service" argument is hooey.
As for "Netflix of gaming"...have you used Netflix? While I haven't - no interesting shows on there - even I know that the only cost is the subscription fee. You do NOT need to pay money to watch each separate show or movie, last I checked, whereas you do on Stadia.