The episode ends with him stumbling down Main Street with his pants around his ankles showing off his polka dot boxers while the entire city laughs at him as the police drag him away
And an extremely petty fuckhead with an easily bruised - something multiple people have exploited (like the guy who purposely pisses Joker off to commit insurance fraud, or Bat taunting him how Harley did his shtick better) - it makes him both very dangerous, but also again, used against him
BTAS Joker works so well because he isn't Batman's greatest enemy - arguably, Batman doesn't have one.
I'd argue that since then, only The LEGO Batman Movie has gotten The Joker right (he's only as dangerous as he is there because he organizes two separate Shitloads Of Villains...)
Really, I dislike the whole Law/Chaos Batman vs Joker dichotomy DC has been trying to do for decades - Batman isn't Lawful and Joker isn't as chaotic as he seems, and their thematics don't mess that well
I'd argue that since then, only The LEGO Batman Movie has gotten The Joker right (he's only as dangerous as he is there because he organizes two separate Shitloads Of Villains...)