My 4 year old boy goes to a day-care where one of the care givers is a man. I know of at least a mother that refused to leave her kid there scared that he was a sexual predator. The same prejudice is faced by male obstetricians.
In the end, whenever you stigmatize a profession as belonging for a specific gender you do sexism, doesn't matter how you do it and who you target.
Crude? yes - inappropriate? absolutely - funny? not in my mind - "against" women? I don't understand how.
I make this distinction because I think about an old professors of mine who stupidly would try to make women welcome by saying things like "Nice to have such a beautiful young lady here". His intent was to make them feel better, but he didn't get that it doesn't work that way.
Note that it included sexual imagery of women, not just sexual imagery. Making a commodity of women's bodies is a big theme of sexism in media, so to introduce that kind of imagery at conference where women will be a smaller percentage of the audience compared to men, you are essentially saying that those women present don't have value outside of their bodies. This kind of thing is hugely alienating.
However it's mostly women that are excluded from more jobs. The idea that "men are excluded and discriminated as much as women" is false.