People laugh when they hear a "sexist" joke because it's funny. Maybe gender related jokes don't have a place at conferences and work places - I am not sure - but there should be room for jokes about genders somewhere, right? I mean, where does this political correctness stop?
Or because it makes them uncomfortable. But in any case, yes, it's true you can make a joke about anything. George Carlin famously proved this with a rape joke. George Carlin was also one of the most brilliant comedians ever to live so he could pull it off. The simple fact is that "jokes" which reinforce current power structure are not good jokes. As a man you don't get to decide how women should feel about scantily…
Famously? People have been making jokes about farse worse matters than rape for millenia. From war, to incurable illness, to genocide, to torture, to the plague, everything has been made into the subject of a joke.
It might be a novel concept for a prudish, politically correct section society, but it's historically true.