What does the launcher do with regard to the operation of the game that cannot be done within the actual game itself? Is it due to a technical limitation or simply there for the convenience of the players? Are there alternatives to such methods of starting the execution of games?
I don’t think I’ve seen games do that, not even to advertise other games from the same publisher/developer. But then, the only five games I’ve played with a launcher are three MMOs, Genshin, and Honkai Star Rail.