Like most of Microsoft’s more odious features, this one can be turned off through GPO/Intune policy across an organization. As such, the liability will mostly fall on the organization to make sure it’s off. The privacy and security impacts will be felt by individuals and small businesses.
They claim that the data is only stored locally, so far. We’ll see, I guess.
Depends on the games you like. It won’t perform well at 4k, or with newer FPS titles. Most games should be playable at low-medium quality settings.