Don’t make excuses for the imam. I wouldn’t be surprised that he’s just afraid of discussing the 3-letter “s” word in a khutbah. He probably doesn’t know how to go about the issue in his lecture.
To say that “It is not a common problem among Muslims” is a weak argument/defense. He hasn’t met every Muslim in the community…and most of the Muslims that he DOES know are not going to admit such problems to him because he’s the Imam. They would feel uncomfortable about being judged, about the religious leader of their community knowing about such intimate details of their lives. How many would seriously confide to him about such matters? Not many. So he can’t say that it’s not a “common” problem. Is he going to argue that “Drinking and gambling and fornicating are not common problems with Muslims…so I’m not going to discuss them.” Is he waiting until an issue DOES become a more common and rampant problem before addressing them? Where’s the logic in that?
He could have made the overall topic of the khutbah to be, Respect in Marriage…or…the Spousal Rights in a Marriage. And he could bring up the topic of divulging bedroom secrets…just for a few moments. The whole entire khutbah does not have to center on this particular point. You could have even argued to the imam that if there’s a “hadith” from more than 14000 years ago in which the Prophet SAWS advised on an issue…then that “issue” must have been…if not “common”…then at least a problem even back then. So how could it not be an issue…in today’s society…considering the sex hype and bombardment in the media.
*****The imam does not know your identity…and if I were you…I’d email him again…and in a calm but firm tone…I’d tell him the above points that I made. I’d even offer suggestions as to how the topic can be addressed in the khutbah. And I’d try to make him feel guilty…(in a subtle way) of thinking that an issue “is not common” considering it was mentioned eons ago…and considering he doesn’t know every single Muslim…and few would fess up to him. If he STILL brushes it off…he’s not a good imam. Even if it won’t get him to change his mind, I’d at least find satisfaction in making him feel bad…and it would give me an idea of him Imaming skills…for future reference.