It looks like you can click through it, so you can still have your sexy time. Based on the description, it seems like its intended to prevent accidents, which seems ok to me.
Look how far we've regressed. Forty years ago if the phone company said it was going to spy on conversations and halt phone sex but don't worry because you can always choose to resume it, we'd never have accepted that.
Is privacy a concern if the monitoring is locally processed? Apple claims it is.
I say it's amazing how far we've progressed. We could've prevented an entire Seinfeld episode if cameras could warn the user of the presence of nudity in their photos.
That distinction isn't important. We could take it for granted that our conversations wouldn't be analyzed for sexually explicit content, and then companies like Apple normalized the opposite. We hadn't yet been fooled by "think of the children".