This, whole, post. All the way.
Honestly, I'm sick of all the discourse and infighting that goes viral online in general, but especially in fandom spaces it seems to be a huge issue.
I used to be in the Tony Crynight fandom up until a couple months ago when I left, and there were so many people fighting about what details were considered "canon" or head-canons, and whether or not doxxing Tony over him changing his animation style was a good idea (actual argument I got into with a member of the fandom btw), and it got so bad that it ended up making Tony's content look bad to outsiders (which they're technically not wrong about that, especially his newer content post-season 1, but still goes to show how one stupid member of a fandom can ruin an entire media for someone nowadays).
Mind you, this is the fan-base of a popularish FNaF animator that peaked in 2015-2019.
There were just so many toxic people and/or people that were only in the fandom purely for "nostalgia" and didn't actually care about the content, plus the gross amount of kids (and phonk edit motherfuckers) who thought that Tony's animations were their regular brain-rot slop content and treated them as such, basically prompting Tony to make more slop content just to stay relevant (happens a lot with youtubers that peaked in the 2010s, TheOddOnesOut being a major example).
And all of it got insufferable enough that it ended up being difficult to even enjoy Tony's content anymore and find other genuine members, which is why I left the fandom entirely (plus mental health reasons and generally I'm not on good terms with a couple of people in the fandom).
I personally blame this on nostalgiabait and Five Nights at Freddy's in general becoming mainstream, mainly given how it's entirely possible that most of the people watching these videos from nearly 10 years ago for "nostalgia" are only really doing so because it's trendy now, and probably never even seen the videos they claimed to see as a kid, making it difficult to find genuine members of the fandom. It's like people don't actually find value in these older pieces of internet media anymore and only care about seeming "niche" or "different", and it's kinda sad thinking about that.
It's like you said, it feels more like a side hustle to gain clout and monetary income rather than something that people just do for the sake of liking the media and meeting other people who also like that media.
True fandom culture is dead, and we are seeing the consequences of that in real time.