Valve ban advertising-based business models on Steam, no forced adverts like in mobile games
(www.gamingonlinux.com)
I'd be most excited if they just worked on SteamOS for phones too...Then the rest of the community could piggyback on that to catapult phone-Linux as our long awaited practical third option!
(And no, Android, especially modern googlized Android, is not Linux or FOSS enough by a longshot.)