It is kind of another beast altogether for Google, Shadow, Microsoft (xCloud), etc. to dedicate actual hardware for your usage. Shadow and others like it are essentially remote VM w/ GPU that you rent by the hour. Stadia, xCloud, etc. we don't know what the business model is going to look like. The only positive here is that Microsoft, Google, and Amazon are all cloud infrastructure companies so in theory, they could price their offerings cheaper than a company that is a tenant on their systems.
Microsoft has made clear that they want Xbox to be a platform independent of the physical box they sell to people. They are 100% going in the direction of Stadia. The big question is how they are going to do it in regards to their next console.
That would be considered unfair competition and they would probably be fined by EU, I guess