They actually have clearly used that cut to improve the infrastructure, which in turn actually helps developers far more than you think. For example, Steam's own controller input wrapper saves developers from having to implement both Xinput and Dinput support, as Steam can handle it itself. Same thing for no longer needing native Linux ports, which has become big in itself thanks to the Steam Deck. Some games have seen huge, immense amounts of purchases (see: Black Ops 3 with Zombies mods and Rivals of Aether) long-term just from getting workshop support integrated. All of this saves time, which in term saves money, which as far as I know, EA, Ubisoft, Epic, and Microsoft Store have done absolutely nothing like this.