Yes, when other people in this thread -- and let's be honest, men -- play the thought experiment where the roles are reverse and it's the wife sitting in the audience, they don't see what's so offensive. "I wouldn't be offended!" they think.
They see a formal symmetry in the situation, but miss the fact that there's a huge asymmetry when it comes to power and gender.
"Here’s what the man introducing Rebecca chose to say"
So, who is this "man"?
Easy to say but hard to do depending on your relationship to the "someone".
Let's say the person doing this is of the stature of PG and you are looking to get into YC.
Is it safe to stand up to him?
Sure that might get you points for taking a stand, he might actually like that.
Or maybe not. It's double or nothing.
It's easy to take a stand when the person being sexist is of no significance to you. Much harder if you have something to loose.
This is why things like this happen many times. And important to keep in mind. Power.