Because of greed. As soon as these online services started appearing, some publishers noticed that you could use such a service to share a game if you take tur

Because of greed. As soon as these online services started appearing, some publishers noticed that you could use such a service to share a game if you take turns playing it. So they added protection to prevent their games from running inside streaming services. Other publishers considered that a VM could be used for circumventing DRM by creating an exact copy of a licensed system. Also, a virtual machine could be used for cheating because now you have an API for video and mouse input. So they added protection to prevent their games from running inside VMs. The result is that Stadia and Geforce Now are effectively unusable for recent high-budget launches (DRM) and for competitive play (cheating). Streaming services are still great for super casual play, but so is a Switch. And for the latter, you can trade game cartridges with friends. For streaming, they don't allow resale or trading due to ... greed, I guess. In the end, no game streaming service had a good user experience.