That particular kind of naivete is especially prevalent on FR. I can no longer remember the FReeperette's name, but on a thread a long time ago, she even postulated that most couples give up french kissing early into marriage. Having been married over 20 years, I assured her that was not the case in healthy marriages, which led to an exchange that left me with nothing but a profound sympathy for her husband.
Having been together close to 30 years, I agree with you.