I'm pretty sure it'll suck because of physics, but it'll be cancelled because nobody cares at all.
Not a single person has said the word "Stadia" to me. I haven't seen a single ad for it. Not a single niece/nephew has brought it up, my son hasn't asked for it, none of my friends are even aware of it to badmouth it or praise it.
What do you need to run it? I assumed it would be some sort of software client, but one of the comments here says you need hardware. Alright. Where do you buy this hardware? I haven't seen the hardware advertised, or in any stores.
According to another comment it's launching in a week.
Where's the buzz?
When MS launched the original Xbox, it was big news. Lots of people talking about how it wouldn't work, but at least they were talking.
Stadia is going to be a complete non-event.
Sure, it'll probably get cancelled, but will we even hear about that?