You don’t seem to have the billionaire monopolist mindset, when you reach the level steam is at you are no longer competing for money but power, steam could be making all the money in the world but that won’t stop Microsoft from shutting them down as they have already tried to do with windows store, if steam doesn’t have its own platform they are vulnerable and beholden to Microsoft, it’s true Gabe Newell could retire anytime he wants but that only applies to him not his countless employees, if steam can’t make enough money to pay a competitive wage to hire people from Microsoft, Nintendo, Apple or Sony then they will just work for them for more money so they have to charge the %30 Steam isn’t a public company but I guarantee the vast vast majority of its profits are poured directly back into the company its always that way or other companies will outcompete and they will die.