Well gen z are old enough to be having kids, and some do. I'm sure they're even worse. But yes, millennials are demonstrably worse parents than gen xers and even boomers.
There are lots of videos on the internet of teachers complaining that the kids just do whatever they want, don't listen and there's no consequence. If the teacher tries to enforce discipline, the school tells them to stop, or the kid's parents will come in and yell at the teacher. I know when I go to walmart there's always kids running around, yelling, messing with stuff, and the parents don't care. That's one of the reasons I usually try to do my shopping on school days during the day, less likely to be kids there.
But these parents just let their kids do whatever they want with impunity because they don't believe in discipline, and not only do they cause problems for society as kids, but they end up being awful as adults as well. Every month we get at least a couple of new hires that literally get fired their first day because they don't understand consequence.
Last month we had a 18 year old and it was his first day. I was tasked with training him and I could just tell he wasn't going to last. He had that 1000 yard stare, which is apparently so common among gen z it's called the "gen z stare". He also had that perpetual nonchalant demeanor. I actually got frustrated with him and said if he kept acting this way he'd get fired and he just said "yeah ok unc". Then he went outside for whatever reason for like 25 minutes and when he came back in the manager fired him. Then he refused to leave the store, cops were called to escort him out and he gave them a hard time too before finally leaving.
Some of these young zoomers that millennials raised are straight up unemployable. That guy that got fired and others like him will probably just live with their parents until they die. Very few people are in a position where they can be a "based sigma". In the workplace you must be submissive. You must take obey and take orders. You also have to have a sense of urgency with most jobs, especially fast food. There is no place in the workforce for a "nonchalant based ironybro sigma male" unless he's exceptionally talented.
The employees we keep are the obedient high-cortisol tryhards that try to work as fast as possible.