Aviation law is concerned with passenger safety, not young children and how they are going to be kept entertained.
Isn't it the best interests of child safety for a child to be sat with who they are travelling?! Rather than some random person!
What happens in an emergency otherwise? You would be relying on a stranger to make sure your child was strapped in and to get their oxygen mask on! Im sure in most cases the stranger would be great but there are reasons that we don't leave our kids and their safety up to any stranger we meet in the street.
From my experience some people on flights get rather drunk. Would i choose to leave my child in the care of a drunk person? No. But if they are not sitting with me then i can't physically care for them so the best they have is drunk person.
What if the stranger says cunt every other word? Pretty sure that the babysitters i use don't say cunt but apparently its unreasonable to expect to have choice over whether or not random person on plane that is forced to have my child sitting next to them is someone i know, trust and know not to be pissed, say cunt a lot or worse.
I've never heard of a child being molested on a plane but it could easily happen, i should know. It can happen in the same room as carers so why not on a plane? It can happen anywhere and in a matter of seconds. Kids aren't even allowed to sit on Santas lap anymore which i think is really over the top considering that the parent is right there with them, but we are supposed to leave our kids on the other side of a plane with someone who the only knowledge we have of them is that they own a passport. All so that it doesn't inconvenience the airlines.