I argue that it’s nothing special.

I disagree given that as far as I know, Valve is the only company in the world that operates this way. I've worked plenty of places where the leadership talked about not having a hierarchy, but none of them could actually pull it off. When push came to shove, there were always bosses and those bosses had bosses, and decisions flowed down from the top. There are probably small communes where they're able to make decisions using consensus, but Valve is a 1000 person company that's a key player in a major industry.