Games

Steam is certainly in a dominant market position. They had a large first mover advantage and have also done a lot of work to make and keep gamers happy with the platform. That said, I can understand companies being upset at the 30% Steam tax on sales. It's a pretty large cut and other stores (e.g. Epic) have tried to compete based on that cost. The problem being that many games have massive Steam libraries and want to keep everything on one place and they aren't really affected by the cost to the devs; so, without a significant reason to change, they won't. It also doesn't help that some competitors (e.g Epic) have been user hostile in the past and so don't have a high level of trust. Steam has also built a lot of goodwill with power users for their work on Proton.

While I do think there needs to be healthy competition for storefronts, as long as Steam resists the temptation to enshitify their dominant market position, I don't see them losing market share in any meaningful way. Perhaps it would be better if Steam were spun off from Valve, putting them Valve on equal footing with other devs. But, video games aren't really fungible. It's not like I'm going to say, "oh darn, Kingdom Come is too expensive, I guess I'll buy Half Life instead". They are just fundamentally different games and if I want to play the first one, I'm not able to get that by buying the second. So, the price of one of them isn't really a factor in pushing me towards the other. Though, Valve might use Steam to push one game over the other, and that could be something that is a problem.