I've often gotten the impression from how Hibari's interactions play out that only characters who were of incredibly high power level even before entering the game are "allowed" to beat him (specific examples being youkai and a powerful psychic), and the best that can be done otherwise is finding a way to get out of his way. That's extremely unappealing to deal with in a character with a might makes right attitude and, in a game where half of the characters become gods on entry, has always seemed unreasonable to me. I've never had issues having CR with violent characters, but that feeling of unwillingness to adapt puts me right off tagging him when I'd otherwise be interested.