I've seen a couple of these in search results while looking for info about more niche games and at first I thought they were fan made but like the article mentions they're not actually wikis, nor do they contain accurate information.
The ones I came across just contained nebulous prose with variously incorrect info about the game on a few barebones pages, with a custom domain name. They weren't using any wiki software.
I have uBlock Origin installed so not sure if the purpose was ads but I was baffled as to what the goal would be otherwise since they're useless for proper information, let alone a wiki.
I think there are people who just assume there's money to be made if you're pushing the sloppified tomorrow hard, and no time to stop and think about why.
Maybe there are other people selling the tools, who try to convince the former people that what they're doing is smart and profit will roll in any day now.
Anyway it would be a mistake to think something is profitable just because someone bets on it.