As mentioned in other posts the discussion was about Tunisia (not Egypt). Since I was there I know that more than one female had to go back to their stateroom and change clothes.
In my
opinion however, part of the Tunisian culture is that women (and men too by the way) can't wear outfits that are too revealing (at least shoulders and knees have to be covered).
The point made on that particular podcast was about the fact that
DCL had not announced this in advance: they even came over the intercom into all staterooms to announce that if you were going ashore you had to make sure you were wearing clothes in which your shoulders and knees were covered.
Even though I'm glad that my country doesn't requires this either, I think you can hardly call this offensive..... it's their culture.