Nobody is saying the joke is acceptable. Clearly it's not acceptable.
But it's important to represent the facts accurately otherwise it discredits us, and can potentially harm what we stand for which is protecting children.
If our message is "This kind of show is inappropriate for children" then it's very easy for people to research and see that it was for adults, and just dismiss everything we're saying, or claim we've got it wrong, or blame us for taking our kids to adult show (along the lines of "silly women taking kids to adult evening shows"). That's why facts are important.
The message isn't and shouldn't be "this is inappropriate for children" but "these jokes normalise paedophilia."
The last thread got derailed with people arguing about exactly how much people standing on random nearby bridges could see, which has nothing to do with the point of the thread: a culture that normalises paedophilia is dangerous.