making a wikipedia-like site involves setting up MediaWiki, which isn't super difficult but does take some knowledge and time investment (and probably paying for a server). Fandom's main draw is convenience and SEO, so you can create a wiki for free in a few clicks and, if it has the canonical subdomain, it shows up at the top whenever someone searches for "X wiki"
making a wikipedia-like site involves setting up MediaWiki, which isn't super difficult but does take some knowledge and time investment (and probably paying for a server). Fandom's main draw is convenience and SEO, so you can create a wiki for free in a few clicks and, if it has the canonical subdomain, it shows up at the top whenever someone searches for "X wiki"
If you have a small enough thing, you can use Amazon's free tier server. Main cost is media storage, the actual wiki part is pretty light.
You'd think someone would've undercut them by now. It's not that hard to make people wikis and pocket the ad revenue.