On an unrelated note, is anyone else having issues with posting? The forums have been refusing to accept my posts/edits over the past day or so.

So I'll apologize for the unfortunate wall of text here as I have been unable to participate in the discussion in real time.

Most of Steam's "competition" are dev-owned stores focused on pushing their own products and are not focused on the larger market. (See: EA, Ubisoft, ActiBlizz, Rockstar, formerly Bethesda...) I consider Steam and GOG to be the only two stores that have seriously dedicated themselves to making a general storefront for the masses (Itch.io deserves an honorable mention, but they are focusing on indies), and I think that GOG would probably be a much larger if AAA devs weren't so obsessed with DRM. But GOG is serving a niche market (which is a good thing), and they are doing that well despite the fact that this niche means that they will command a smaller market share.

I don't like the death of physical PC games either, but to be honest/fair I don't believe that's the result of Steam forcing anyone to do anything. For starters, DRM was already running rampant which was/is still causing physical copies to be bricked thanks to Microsoft ending support for DRM due to security concerns. So physical gaming was on life-support anyway by the time Steam came about thanks to an existing focus on intrusive DRM. Secondly, greedy devs looking to maximize profits at the time saw Steam's 30% cut as a huge improvement over the distribution cost for physical goods at brick and mortar stores (which I think was more than 50% but I can't find any references at the moment on how much of a cut a big box physical release would require). Finally, clearly nobody except for Valve wanted to put the amount to effort into making a viable storefront at the time. Sure, people tried, but making a successful storefront required Valve to practically exit the game development market in order to focus on Steam which is something that the other players weren't willing to do. Instead, Valve made this nice shrink-wrapped package of a storefront, online DRM, and a far lower cut than the rest of the existing retail market which is why everyone rushed to Steam. So while I hate this shift away from physical media, DRM companies would have put an end to it themselves with on-disc DRM had Steam not come along first.

I haven't seen anything about Steam requiring people to use Workshop. It has always been optional and does not prohibit people from posting mods elsewhere, AFAIK. To me, Nexus Mods is currently and historically the de facto market leader with respect to mods, and there are a lot of open-source mods that end up on GitHub, etc. So I don't really understand why Workshop is being called out specifically here. I take far greater issue with Bethesda's paid mods nonsense.

IMO, Epic's failure to capture significant market share is the result of very dumb decisions on Epic's part. From the start they have put more focus on promoting their service to devs (through a lower commission, exclusivity deals, etc.) while at the same time antagonizing the players (by lying about lower prices thanks to the lower cut, by doing platform exclusivity deals, by not actually spending money/effort in making a compelling storefront, by requiring an Epic account for Steam games, etc.) So that's on Epic for not fostering a userbase like Valve did. It also shows that it's pointless to try to moneyhat your way to the top with a product that's not compelling in the first place.

And who controls this achievement/cloud save/mods API? Someone has to, and they will most likely monopolize it. But even if it was created by a consortium of companies, there would still be smaller companies who want something different. Do these smaller players just get forced out of the market for wanting to do something above/beyond the status quo? The fact is that there no such thing as a neutral, one-size-fits-all API for anything. Requiring everyone to use the same API would definitely stifle innovation, and seems like a massive barrier to entry.

So basically you're advocating for a hard and fast government monopoly on APIs where they do own the market and can/will abuse their power? Government money is still big money with the same wealthy types at the top calling the shots for personal profit.