they don't push steam DRM...devs choose whether they want it or not

If you want to sell your product in a store, your product has to abide the stores rules. This is nothing new. You don't get to whine about how you can't sell enough anywhere else because customers prefer buying from the store, that's asinine.

30% is the standard cut for game sales across the industry. Epic has a smaller cut, but customers don't want to use it. As someone offering a product, you have to sell where your customers are. Steam COULD abuse their position by taking a higher than standard cut, but they choose not to. Steam isn't a bad guy here. They made a good platform that customers prefer, and have made no attempts to stop competitors from competing and despite having the market position to abuse it, still only charge the industry standard for selling on their platform. If anybody would bother actually trying to compete with them, then you might see the cut come down, but all their competition seems content to just whine instead of actually making a platform worth using.

Steam provides not only a storefront with lots of features that devs can use, they also provide servers, backend support through different APIs and not to mention the insane amount of data users need each day. (Around 275 PETABYTES a day, or 100 exabytes a year) That kind of infrastructure is not cheap, and seeing as that was the industry standard (it's still what Google and apple get from their storefronts) I'd say that's pretty reasonable.

Also the 30% cut goes down to 25% after the first $10 million in revenue, then down to 20% after you reach $50 million. I do think they should put in a lower cut for independent developers who are releasing small games, until a certain revenue threshold is reached, but overall I would say it seems reasonable to me.

That 30% is industry standard, steam didn't even set it. You people are morons

That is also something that would allow a competitor to come in to outseat their dominance. In fact, charging 5% instead of 30% would make it much more difficult for competition to develop because it would be next to impossible for somebody to penetrate into the market by offering a lower rate that's only viable with huge volumes of sales. Usually, offering unsustainable prices is a way that a dominant player achieves a monopoly. If they have big cash reserves, they can run at a loss until their competition dies out.