The technology works, but the business model doesn't, so there's the eternal risk that it might get shut down at short notice with no way to export your saves.
Yeah, that's definitely a worry. Also, the fact that you're dependent on them for adding support for future games, and that (like any cloud service) it might not be available right when you want it.
Yeah that's the issue - nobody wants to just rent you a gaming PC in the cloud, they all want a cut of game sales/licensing. But if someone were to do it, the technology is absolutely there.
You don't even need to create any internal tech - Steam Remote Play already has everything you need, and I successfully used it to play Battlefield from an AWS GPU instance (was even good enough for multiplayer).
