I think many if not most people will have negative associations when they think of adult anime enthusiasts, therefore most people with good social skills would not put anime on their LinkedIn.
I also probably wouldn’t want to hire someone who’s holding a gun in their LinkedIn photos (unless it was related to their work), even though I’m a hobbyist shooter myself. I think shooting is a cool hobby, but I understand that for many people it’s a weird enough hobby that it would be downright stupid to advertise it in an unrelated professional context.
The problem isn’t anime (or guns), it’s the poor judgement demonstrated by adding pointless question marks on what might otherwise be a good profile.
Though, I don't know: would putting any film background on a LinkedIn profile read as "unprofessional"? (I don't know; I've never used LinkedIn in any capacity.)
I think it really depends on the film. I doubt the expected value of putting a special background on your LinkedIn profile is very high.