I have several friends who used to work at Valve none of them hate the place, they still have friends there, etc. But they tell similar stories as to why things that normal companies do successfully are impossible at Valve. Perhaps it’s best summed up by something one friend said about her year and a half at Valve: “I first learned who my boss was on the day she fired me.”
Google tried this, notoriously dense grating and then firing basically all the managers at an all-hands. That didn’t work out well at all... And now they have over-steered in the opposite direction!
The failures of other companies trying to emulate or capture that market do not a monopoly make. There is no real moat for Steam beyond customer loyalty and the fact that nearly every competitor sought to gain market through anti-consumer moves (exclusivity) rather than value-adds, and almost universally with shittier software to boot. There are a few notable counterexamples (GoG is a good store, value add, respectful of customers; but just didn't have the juice to establish itself beyond indie/abandonware games; Itch.io is doing fine in its niche).
Just because customers prefer a product does not mean it's got an unimpeachable moat.