Being the most favorable game market does not mean “there is no competition”. It’s just the competition is doing it wrong so everyone flocks to what they like or have stuck with.
I do think the 30% commission is high. But the problem I see now is, even if the gov’t gets involved and mandates their rev share be lower, game publishers will absolutely not lower their prices to coincide with that. Corps know people are already used to paying pretty exorbitant prices, so they’d happily have the government mandate they make more profit while valve makes less without having to do any work whatsoever.