I think you're view will change when you start putting numbers on it. I'm going to talk about the games in the app store example because it's the instance of the problem that I first thought about and it is easier to put a monetary value on an app than on a comment.
Let's suppose Apple wants to make sure every game in their store gets at least 5 ratings. To do this they are going to pay people to play each game for 5 min and then assign a rating. In an hour a curator can get through 12 games. Over an 8 hour day thats 96 games. Apple would need to hire about 7 (iirc) full time employees just to give every game one rating. We wanted every game to have 5 ratings. Assuming that users on average provide one rating (but sometimes 0), we still need curators to provide the other 4. That means Apple would be employing 28 full time employees just to get their content minimally curated.
Let's use the salary from the article and say each curator costs 30k a year. That means this whole department of curation is going to cost about 900k a year.
Most of what they are sorting is going to be shovelware anyway. To justify the cost of this department, the curators need to find gems, content that's really good but would have otherwise been looked over. They need to find 900k of gems per year. Considering the average earning of an app, this is just barely plausible. If you want to do anything more advanced with your curation, like have the curators generate key words or figure out which demographic might like it, your budget is blown for sure.
IDK how the economics of comment curation works out, but I bet it's even worse. After all, no one is even paying for comments, and making a comment is way less effort than making an app.
