I strongly disagree. I see your point when it comes to laughing at someone's expense and someone being upset with it, but that doesn't necessarily mean that would happen in all cases unless it were some malicious diatribe.
I don't think you can generalize the correlation to humor and hostility so easily. I know that simply mocking someone and having that be the root of it all humor wouldn't add up when you consider there are people that just unironically say awful shit to someone for the sake of it and some how consider it to be a joke when there is no irony. I don't know man, maybe it's all in my head, I'm crazy, need help and all that shit but I think there's a difference and can be dealt with without sacrificing anyone's ability to simply mess with someone.