I would contend it's quite the opposite, it's the adoration of women and putting them up on a pedestal that makes the 'yo mama jokes' even exist. The underlying

I would contend it's quite the opposite, it's the adoration of women and putting them up on a pedestal that makes the 'yo mama jokes' even exist. The underlying theme of the joke being that the target would be insulted or feel slighted by the references made to his mother. This implies that the target cares about his mother or least cares about her reputation. As to the choice of adjetives, they are almost by definition negative in connotation. A fat and ugly does not seem an equal alternative in terms of value to a regular man, hence those adjetives devalue both genders. You could make a case that those particular adjetives devalue women to a greater extent than they do men, that's sexism, not misogyny. The reason we don't see 'yo papa jokes' is because stereotypically people won't defend or get riled up over what's said about their fathers. I interpret the attacks as targeting something that is valuable, much like a terrorist tries to blow up a landmark (despite the security) and not a shack out in the boonies (because it's defenseless). I contend that socially, biologically and culturally speaking males are predisposed to protect women because they are valuable (and in certain lights, more so than males). So no, I do not believe this is misogyny, far from it. I do, however, believe it is sexist.