I was off the Anthems of the Seas on 24 December. I would say it has similar demographic to what you observed. In fact, I shared some of the observation you experienced.
The buffet was a zoo during breakfast and lunch.
Crappy weather and heavy waves.
Once per day cabin services.
Lines everywhere for activities like bumper car, laser tags, etc.
Though, when I compared with your notes, I guess I justified paying the "premium" that Royal Caribbean charges over MSC is when things goes wrong how they handled the issues. I also had an issue with my premium, but they showed up at my cabins within 10 minutes, apologetic, somehow found another adjoining cabins when the ship is sold out and offered compensation without being asked. Also, I don't have any issued with the services received from the dinning room staff, or the cabin crew, nor Casino or Bar staff.
After having your review, I'm a bit nervous with my March break cruise on the Merviglia. Though, MSC was charging one third of what Royal Caribbean wants for the same week sailing out of Bayonne. I have a very low expectation on my very first MSC cruise, so hopefully, they can somehow manage to at least meet expectation.