[user104658]

I wouldn't say "equally" and violence is never justified, however I think the joke was massively ill-judged. That said I actually don't think that was intentional, he thought he was just doing a "basic roast" and hadn't given enough thought to the likely implications. Alopecia often has an underlying cause rooted in some extreme emotions/stress/trauma... but then, there's no reason Chris Rock should know that so the appropriate response would have been for Smith to let him know respectfully afterwards that it was not well received. Chris Rock could then have apologised (either publicly or privately).

Having typed that, I'd actually change to Chris Rock being more justified... as while the joke was poor / in poor taste, it's still "justified" to try to crack jokes in that presenting role (it's expected) and it being a BAD joke doesn't change that.