I've come to a conclusion.
Valve's real problem, is that people expect something from them that they are not trying to provide. Everyone on here is complaining that Valve needs to do more to reign in the developers, because it's Steam's space and the publisher's are just guests there. However, I don't think Valve regards the game pages as Steam proper--it belongs to the developer, and Steam just provides the hosting service.
Everyone keeps admonishing Steam because it's not structured like Amazon or Newegg, but that's not the business model they're going for. The business model they want is "YouTube, but for games." Let whatever crackpot creator who wants to reserve space reserve it, host the stupid cat videos alongside professionally produced content, and let user and subscribers decide what gets popular. The only real difference is that YouTube takes a cut from the ad revenue, while Steam takes a cut of the sales revenue (since games don't sell ads).
It's like the difference between YouTube and (say) Amazon Streaming Video. You can certainly make arguments about the merits of each, but everyone is coming into the discussion assuming it's Steam's end-goal to be a STORE (like Amazon), when what they're really trying to do is be a HOSTING SERVICE (like YouTube).
In this light, their policies regarding developer's comment threads and lack of QC makes sense--I mean, the Air Control dev owns his page, just like the big boys own their own pages on the web. Let him edit it as he sees fit--it's his chunk of the web, after all--and the community will put him through the ringer if he missteps. By the same token, QC doesn't really make much sense under the YouTube model--after all, who's to say Air Control wasn't the next Double Rainbow of video games?
Valve needs to figure out a way to change people's perceptions of Steam. It's hard because for one thing Steam didn't begin this way--in the beginning, it was a curated store running a classical model of distribution. Second, Steam is the only place distributing content this way, which makes comparisons to other services less apt, which colors perceptions. If they could reshape perceptions it would help greatly--people might not like the model Valve's adopted, but at least they won't be pissed off because Steam isn't even trying to meet their expectations.