So, if wimpy effeminate Michael Jackson were to b!tchslap Lucy Lawless, the really buff actress who played Xena, who could supposedly take it without serious injury, that would be funny?
My mother-in-law, a passive-agressive lady who's husband is a recovering alcoholic (30-years dry, but she's not forgiving nothing) simply LOVES the Funniest Home Videos where a guy gets a brick right in the "meat and two veg". You don't have to be Freud to get that one.
In my experience, it's nothing but taking a cheap shot by promoting a cheap laugh by using a cheap gag. Some things ought to be off limits. No one would think of getting a laugh today in the movies by showing a black person doing a minstrel show, a stingy Jew, or "playfully" slapping a woman around "because it is funny." If we are going to "respect" people, then it should be everybody, and I don't care if the Left drags out the "its funny because men are evil bastards and deserve it" excuse. It is no more funny than "America deserved what it got on 9-11".
It's also a potentially lethal blow if it's hard enough.