irl or even online? Do I get to count manga? If the latter and yes . . . uh, I don't think I've met a single person who likes Tenkaichi even though it's genuinely one of the best manga currently running. No Kengan Omega fans either, though it's not half as good imo. Also that one about the Detective Novel club, Versus, and, well, I guess I'd be here all day listing them all

If it's just anime, I've never met a Kengan Asura or Blue Lock fan, so there's that. Yes, I know Blue Lock is obviously proto-fascist, but it's still interesting here and there. I also think "The Misfit of Demon Academy" is unintentionally one of the funniest anime ever made and I don't know any fans of it. I can give it a thonk and come up with others if you're really interested, but I think that's a decent enough list to start.

PTSD Radio (manga) is another fun one. As an aside, my list is way shorter than it would otherwise be (Great Pretender, Paranoia Agent, a few others) because usually when I really like an anime I force someone else to watch it.

Oh! Blood Blockade Battlefront and Akudama Drive. Those are both really fun, well-animated action anime that I have never met a fan of.