That’s a complex subject, and I’m not really up for a deep dive. (Plus I’m in the middle of resurrecting the hard drive with my database of references.)
First, when I said cult, I was mainly thinking of Scientology, but I admit that I hit JW with that remark. Second, cult is a very shifty word. What does it actually mean, beyond the usual pejorative one? (It’s usually avoided for that reason, with cultic group or new religious movement used instead.)
First stop, Lifton’s eight criteria:
https://www.cultrecover.com/lifton8
I think the JWs checks a lot of those boxes. I could provide many examples of organization problems detailing that, except that I can’t right now. /bangs head on desk.