I won't say no to cheaper games. The 30% cut was settled upon in the days where physical copies were the norm and Steam was still under heavy development. Given how established Steam and digital distribution in general is, it's not really fair to developers to dedicate almost a third of the price of the game to a hosting platform. Yes, exposure is important, but that's a service provided passively due to the fact of being the largest platform. Reducing Steam's cut hurts no one except maybe Gabe's ability to buy another yacht (and even then, not likely). Even if customers don't see lower prices if Steam were to reduce their cut, it'd be great to see the actual developers getting more money from the games they put all the effort into making.
They being the largest platform because the consumer wanted their service, not out of obligation. Epic provides cheaper cut for the developer and is steadily building up their library. But why don't users flock there? Heck, they even have some actual exclusive titles there. EA and Ubisoft too got their own store, and they too got a few exclusive title. So why does steam is still being chosen? Maybe there is other value provided besides hosting, like, idk, remote play? Controller remap? Family sharing? Opening linux gaming market? Social feature? Forum? Modding?
Momentum. Steam was among the first on the scene and provided the best experience. Thankfully Steam has kept the momentum going instead of enshittification (thanks to being a privately held company), but almost a third of the price of the game is still ridiculous if you consider the effort that goes into making a game vs maintaining a mature platform.
I mean, did the competitor even make an announcement to have at least feature parity with steam? Last time I heard, GOG doesn't have regional pricing, Epic is not supporting linux just because, and EA/Ubisoft is just a glorified ad