But if it's not about the content, why are we here then talking about how Apple needs to validate the games sold inside a game streaming app to be App Store pol

But if it's not about the content, why are we here then talking about how Apple needs to validate the games sold inside a game streaming app to be App Store policy compliant. Youtube isn't necessarily too far off from game streaming, technically speaking. Both transfer video content over the internet. And the game streaming app doens't install anything, not even the games, to your device, as that's the whole point. I'll also add that why can I watch the game on YouTube when some youtuber plays it, but I cannot purchase & play it remotely through this one app? And do note that you can purhcase movies from Youtube app.