because of the anti-competitive price restrictions that Valve often imposes on game developers and producers (the Price Parity Obligations). This means a publisher or developer would not be able to list a game on another platform as well as Steam, unless the prices offered on Steam is the same or lower. This applies to games on all other distribution stores (including online and physical stores) not just those distributed by Steam Keys

Textbook anti-trust lawsuit. Different from what Epic does, I doubt they impose such rules on developers.