I could have written this exact post.
I have two small kids - when we cruised in February they were 4 and 18m. I LOVED it and started looking at when we could do it again and did a lot of comparing to other lines. When you have small kids that still nap, the room setup is really important. We stayed for a few days in Puerto Rico before our cruise and having all of us in one big hotel room was a disaster. Once we got on the boat though, it was sooo much better. For one, the kids are separated from the adult area with the privacy curtain. Two, they were separated from being able to see each other because of the bunk/couch setup. I could move freely in the cabin, watch a show on my computer with headphones, or read a book and they couldn't see me and just went to sleep. I've seen pics of lots of other lines where the bunks are literally on top of the main bed, there's no curtain, or the couch pulls out into a double bed (instead of having two separate beds for kids). I also found the ship (unsurprisingly) super kid friendly. I didn't have to worry about my 18m old's behavior at dinner, both kids had pool/water areas they could go to, and the shows were kid friendly and a good length. We also loved the nursery and the kids club and had them go a few hours total over the course of a 4 day cruise.
Not everyone will have the same needs that we do. People find value in different things. For us, I am willing to pay a certain premium for this kind of experience. And no matter how cheap a cruise is, I'm not going to go if my kids will be sleeping over my head. With Disney I could spend a lot of time in the room and still feel some separation from my kids. If they were over my head all night and during nap time I'd lose my mind. Our 4 night repo cruise from San Juan to Port Canaveral was about $3300 for 4 people in a verandah room, and we did not book on opening day. I highly doubt there's a cruise out there for $1100 that would be comparable.