I feel like it's more than a handful of areas, though I'll grant there are plenty where academia or mainstream media outlets are the most reliable/trusted source. If you're talking about astrophysics, the history of the eastern Roman empire or the US' government foreign policy, the Wikipedia setup will work perfectly.
On the other hand, if you're talking about Star Trek, the MCU, Taylor Swift or the Legend of Zelda series, the most reliable source is probably not going to be either an academic journal or the New York Times. Many of my videos and articles are about games in the latter series, and the reliable sources for that would probably be something like speedrunners, dataminers, etc. For most of those things, the reliable source would either be the artist or company that owns the rights, or some fansite/video creator that's been documenting them for the last three decades.
Plus, a lot of the time the sources Wikipedia accepts are just laundering the same info anyway. It would be very, very easy to get misleading or incorrect information about the next Pokemon game to go viral, just by sending a few publications a link to a random blog and letting them take it at face value. In a depressing number of fields, fact checking and research is minimal even from name brand publications, and some guy's post on Reddit can get treated like gospel.
> if you're talking about Star Trek, the MCU, Taylor Swift or the Legend of Zelda series, the most reliable source is probably not going to be either an academic journal or the New York Times.
You lost me here. I mean, yes, there's serious fan community interaction around those subject which is unauthenticated and anonymous. But that's interaction and not research or journalism. You might cite the existence of a favorite lore or fan theory in a wikipedia article, but you don't take the fan stuff as a source for the original material!
To take your specific example: Swift is literally getting married today, I gather. Why do I gather it? Because trusted human beings in my information space (Twitter feed, news articles, etc...) are telling me! Would I trust an anonymous fan source telling me someone got married? Almost certainly not.