It’s definitely more subjective than a lot of folks around here are willing to admit.
For myself there was a lot about cata that I really enjoyed. The zones, story, dungeons, and even Tol Barad and Firelands. It all felt pretty epic, engaging and fun.
WoD was also fun and I liked most things about it. Just wished there was more of it.
Shadowlands however was my worst WoW experiance. I hated the idea of being in the afterlife but still killing and looting and skinning and mining and what have you. Just felt beyond stupid and the zones just weren’t very nice for my tastes. Bastian or whatever it’s called had too much random crap floating in the sky. Was a very messy and amateurish looking “fantasy-scape”. Travel was a nightmare, story was… I’ll just say it didn’t catch my interest at all, I even remember the music and while a few things around Ardenweld were pretty, that was basically it. Everything else felt awful. To me at least.