You really need to check what the word "innovation" means, my friend.
And I'm glad we agree that the Portal link you started off with was useless, since you're now iterating to something else. Steam Play, while a great idea, is different from Play Anywhere. We both know that.
I'd like you to explain how you think Steam Play is any different.
You buy a game on Steam and it allows you to play the game across all hardware where the Steam store is officially available for playing games (Windows, Mac and Linux).
You buy a game on Xbox and it allows you to play the game across all hardware where the windows/xbox store is officially available (windows and Xbox consoles).
Just as Steam play only grants you a copy of the game to play across multiple device types that run Steam, Play Anywhere only grants you the PC version via the windows store (which nobody in their right mind wants to use) and Xbox consoles (the less said about that the better).
You are literally only getting access within the
same store that Microsoft themselves own (for example, you are not also being granted, Linux, steam, playstation, etc versions of that game). Which, incidentally, is exactly the same thing Steam has been doing with Steam play since 2010 (although they did make an exception with the PS3 version of portal 2).
"New to Xbox" does not mean it's new to the industry. But we've been here many times before, just as when people really tried to tell us gamepass was the first gaming subscription to ever exist.