Which is a completely different, and rather trivial, problem compared to "automatically detect the age of people in a video and/or if they are doing something sexual".

The first is a mere process of comparison, while the latter requires quite a few levels of subjective abstraction.

> copyright because of background music

I feel you. Many of my videos have been flagged for copyright violations due to background music, but since they are unlisted and only for sharing among family, I'm ok with it.

There have been a couple of times they have muted a whole video for a snippet of music, but I've never had a video removed for music.