Hmmm I definitely agree with where you went at the end but I think there's a better comparison. Tool is one of those bands that musicians are really into. The way they write is deliberately technical in a way that non-musicians can enjoy but musicians geek out over. They really like "the process"
Sleep Token fans, from what I've seen, just really like the music. The fandom seems like a combination of any rock band and a pop star where there isn't a big percentage of self-proclaimed music experts. They're a lot less self-important, they just think their favorite band fuckin ROCKS.
I admit that's all anecdotal. And full disclosure, I dislike Sleep Token and used to really like Tool