Others have also expressed their wish for this as well, thus I’ve moved your post into this Feature Request topic.
It is also a concern for me, not so much from children in my case more from having guests round that could accidently wipe albums from library.
I have to confess I’ve even deleted the odd album myself … fortunately I have a backup (or two) so it could be recovered. However, it were someone else that had deleted … it could be months before I noticed and possibly my backups by then would be stale.
On my previous streaming system Sooloos, I had library management and setup functions PIN protected.