Wtf is with people deciding a monopoly is good because the company hasn't started enshittifying it yet. It will happen. It's what monopolies do. Healthy competition is an important part of preventing enshittification.
Steam has no competitors because nobody is competing with them, not because they are forcing nobody to compete with them.
Steam isn't abusing their dominant position to prevent competition. Other companies could make their own storefront and compete with steam. Nobody does in a way that's actually comparable to steam.
Steam has a monopoly, but it's not because steam is actively keeping it that way.
If you have enough control on the market you don't have to actively try and stop competitors, you're just the default solution and people automatically turn to you. Walmart doesn't need to use dirty tactics to compete against mom and pop shops, the day they open people just start going to Walmart instead because they have everything in a single place.
That wasn't always the case, and I don't know if it's currently the case. At least at one point, they would intentionally lose money by dropping their prices below profitability just to get mom and pop shops to shut down, and then raise prices back up to profitability. Or they'd force suppliers to cut costs only for them to the point where the supplier wasn't making a profit, but by then they had stopped selling to competitors.
There's a lot more evidence for Walmart committing anti-trust than Valve.
They won’t lose money if they lower prices of key products in one single store and just a bit lower than their competitor the moment it becomes a threat. And even if they did, they would make it up later by having the whole market share. It’s no different than, let’s say, Uber burning money initially to win against all competitors then raising prices when they become the default platform people trust.
They know that after they have the market, it takes a significant upfront investment to bootstrap a competitor, which can only be done with investors money, which at that point won't bet on the smaller company with a boring business model.
Point is, they don't need to do that now because they're dominant, they just have to come in with their big boots, sit at the table and wait until everybody leaves, they have unlimited money, they just need to offer the same prices as anywhere else, the convenience will kill the competition.
Nobody can because of Steam's monopoly. You can try to create your own store but you won't have nearly the same selection of games. Monopolies are bad. Even when they're companies you like. To be clear, I'm not saying Steam should be broken up, I'm not saying they should lose games to other stores. I'm saying they're a monopoly, and that is bad because it enables Steam to stagnate or even get worse.
It's also pretty inarguable imo that Steam has been getting worse. Steam sales used to be events. You'd get multiple huge discounts on AAA games. Now you're lucky to get 40% off a 6 year old game. And don't get me started on the UI, which, while fine, hasn't changed meaningfully in like a decade. There simply is no incentive for Steam to be better. So they're not. We should consider ourselves lucky that they're still as good as they are, because they won't be forever.