Sure, and my somewhat cheap response misses the subtleties, see my response to JohnnieCache - at a conference with women in attendance and slides/etc. with an obvious 'aren't these women fucking sexy we geeks don't get much of that do we? Haw haw' edge to them, are such 'jokes' really making light of sexism or not? I think very much the latter.
The problem I have with your cheap response is that it actually clouds the issue. The question you and me should be asking is "why would it be appropriate to have sexist (or rather offending) jokes in any moderately public setting?" You're getting side-tracked by your parent who intentionally(?) uses "political correctness" and a move to a global statement as a way to stifle the discussion about why the jokes in question are certainly inappropriate for a public audience. It's not a question of "which jokes are we allowed to tell?" but rather a question of "are we allowed to offend participants on a conference/meetup/...?"
