Children model the behavior of their adults including entitlement, rudeness & lack of civility.
DCL's lack of policing guest rude & unsafe behavior is a lesson to kids that you can get away with anything.
After 16 DCL cruises going back to 1998, it's been the last 8 years or so that we've seen more abhorrent parent behavior. One fight so bad at the fireworks that a man was beating another with his belt claiming the man blocked his view--took quite a while for DCL staff to respond; a couple so drunk & loud in Skylight Lounge that that they were falling off their stools--the bartender kept serving them as other passengers fled & the cruise director ignored them; parents sitting in the adult pool next to the pool bar late in the afternoon with their empty beer buckets around them watching their two kids fling deck chairs--no DCL stuff ever appeared; etc.
We have sailed on multiple other lines at various times of the year; DCL is the worst. IMHO It's because Disney markets the "perfect family cruises", the codeword for parents to leave their kids in the clubs all day, have dinner with the kids on their tablets then send them right back to the clubs until bedtime (they DCL staff even come get them from the dining room); this leaves the parents time to relax without a thought or care to what the kids are doing. There's even a kid's club on CC & parents can leave on an excursion in port while the kid stays onboard in the kid's club!