Why Facebook's new rule about sex is its weirdest yet

Facebook has always taken strange positions. But what is the point in banning posts that 'facilitate, encourage or coordinate sexual encounters between adults'?

Facebook has new rules, and they are not fun; like Dua Lipa's, not fun at all. You could not dance to these rules. You must henceforth desist from any post that could "facilitate, encourage or coordinate sexual encounters between adults". Since sex between consenting adults was, last time I checked, legal - indeed encouraged by responsible media platforms such as ours - this struck me as peculiar. Facebook has always taken strange positions: for ages, the weirdest was that it would remove pictures of breastfeeding, but not pages that made light of rape.

This is the strangest yet, particularly given Mark Zuckerberg's well-known creed of do-what-yer-like. If he can withstand the pressure of parliaments across the globe to appear before them, and if he can weather every accusation with a sturdy, "No, I didn't " OK, yes I did, but I won't do it again," which special-interest group can possibly have leaned on him to make this radical move? Which evangelical church, which celibacy movement, could have got under his skin?