Didn’t you just post this? I’m guessing you deleted the first one by mistake?

Anyway, lots of people dislike him because he has a pity mechanic. Some find it disingenuous for a character to be rewarded so heavily for being hit. Even if he's not broken, one can't help but question how much work the opponent is having to put in when they're main is being buffed up to top tier for being outplayed. Others have issues with some of his moves such as his ridiculously effective counter/reflector and his gun which is capable of shutting down some recoveries by itself.

If Joker was as viable as other characters with pity mechanics like Lucario, his Rebellion Gauge wouldn't ruffle nearly as many feathers.