I'm game developer, co-founder of my own company and I hate Valve 30% cut.

Yet Valve did nothing to stiffle competition. Their only major requirement for games published on Steam was that games suppose to get same efficient discounts as they get on other storefronts. E.g you cannot constantly sell your game on Epic Games store for $10 while Steam version cost never drops below $12.

Also game developers are allowed to request sane amount of Steam keys for free and sell them elsewhere while pocketing all the profit while Valve covers all the distribution costs.

Epic Games stiffled itself. Their store is shitty and dont even have player reviews. No surprise they have no customers except those who come to play Fortnite or get free games.