It depends on which part. It is certainly heading down the same route as Wikipedia with all the problems that entails. You're usually better off on a smaller Fandom wiki as it won't have beeb taken over yet.
The James Bond wiki is particularly bad, but Memory Alpha seems to be better run.
Well at least Wikipedia doesn't pester you with tons of ads that sometimes make it hard to even find the content (except for the occasional donation banner, but that's a minor annoyance compared to what Fandom does).
Some few months ago I couldn't find actors credits for particular roles they had in Star Trek franchise. For whatever reasons these bits were removed but still were present within Wayback Machine.
Then again, in the past I've seen hostile take-overs of fan made wikis into wikia/fandom "infrastructure". In one case wiki was copied, in time articles were slightly edited and new content was added containing... unsolicited fan theories.
The other case: wiki was copied 1:1 due to some inside disagreements, then incorporated into fandom and in approx. 2 years abandoned. The original died as well but someone managed to restore it from Wayback - this time in read-only mode
I have no idea what happened behind the scenes, but Memory Alpha used to have its own hosting and was migrated to the hosted wikia, I think between 2010 and 2015. The old domain still redirects: https://memory-alpha.org/
The main issues I have are with the administration. I have noticed:
* Admin enshittifying content that they have no knowledge or interest in. For example, I have witnessed admin trying to get articles about certain rugby union teams deleted, because they were amateur. (Before the 1990s all rugby union was officially amateur, and some notable clubs still are, especially in places like Argentina or Scotland, where professional clubs are not the norm.) They succeed in many cases.
* Administrators may develop a particular dislike for a user, and their decisions may be based on that. I have witnessed personal vendettas and stalking behaviour from them. There are also cliques of friends and other conflicts of interest.
Neither of these are professional if we are thinking purely in terms of content. Encyclopaedia Britannica, for example, would get articles cross-checked by people who have an interest or a knowledge of that particular subject. I have seen quotations "corrected" on Wikipedia from their original wording.
As for Fandom, it varies from site to site. Some are better than others. In recent years, Fandom has adopted some community guidelines which are questionable and are being applied across the board. Wikimedia did the same in a top-down power move with no mandate whatsoever. It was a fait accompli. Neither are better for it.
The Broad Scots and Scottish Gaelic Wikipedias both have horrific administration issues, brought on partly by people correcting native speakers. The former created a minor international scandal in the media. The Greenlandic Wikipedia was hijacked by a German who ended up shutting it down. (He deleted other people's articles constantly, instead of improving the content and then wondered why he was the only person left in the room.)
Either way, both remind me of the infinite monkey idea... Except those on the typewriter aren't even getting peanuts unless someone is paying them to write shill articles (and there are many of those.) I'm sure I'll be voted down for making these comments which is why I was reluctant to post earlier.
The James Bond wiki is particularly bad, but Memory Alpha seems to be better run.