The reason is all the competitors that have started up have come at it from a perspective of "why owning the platform would be good for competitor X" and not why it would be good for users to use their platform. And so the only ones that have managed to hang out with any relevance are GOG for going DRM free and doing classic game restorations, Epic and Game Pass for bribing people with free games. And even the latter two have issues getting people to buy games they aren't getting for free.
The reason is all the competitors that have started up have come at it from a perspective of "why owning the platform would be good for competitor X" and not why it would be good for users to use their platform. And so the only ones that have managed to hang out with any relevance are GOG for going DRM free and doing classic game restorations, Epic and Game Pass for bribing people with free games. And even the latter two have issues getting people to buy games they aren't getting for free.