EDIT: then again circle jerks are more common in some places than others.
Rap music is a genre. If you said "rap music that talks about running around murdering police officers", despite the fact that no police officers were murdered in the making of that song, it would probably also be offensive.
Do you mean ever, or do you just mean to you (or in a group conversation in which you are taking part)? Because the latter would be absolutely fine. You don't want to talk about that, no worries. I won't bring it up. What's the problem with that?
Being a creepy greaseball is not illegal, we have social ways of dealing with that. But this wasn't that situation, it was a more serious one, because these were subordinates he had control over; in that position it's just not ethical to push people to talk about porn and to accept your announcement that you want to grope them. And it's bad business when we are talking about people who were not hired as prostitutes but as long-term assets for the company.
The thing here is understanding context and the way other people's feelings need to be respected.