Ehh, the gungeons in 4 had just as much in them as 5. You had treasure chests and enemies strewn about. 4 just let you get straight to the combat, whereas with 5 you gotta go through all this other stuff to get to the meat and potatoes. Only real thing 5 has that 4 doesn't is will seeds and having a out of the way collectable could be done In a procedural dungeon. Also the dungeons in 4 had tons of atmosphere. Each had there own music and designs. The bath house was very distinct from the underground base. The princess castle was very different from the club. Even if they were all procedural generated they each felt very distinct and unique from one another.I can respect that take, but abso-fucking-lutely not. I ADORE the palaces in 5 due to how unique they are, gimmicks and all. I felt the opposite, going back to Persona 4 for the first time after 5: I couldn't stand the dungeons. They felt like boring, empty hallways with nothing but combat in them, no crafted design, no character. Just bland things that you wanted to jam through as quickly as possible to be done with. Whereas in Persona 5, I could just hang out in dungeons for hours (and did!) with how bespoke, charming, and atmospheric they are. I would hate going back after P5 gave us some of the best dungeons in any JRPG ever.
Royal would have made me very happy if there was an option to switch over to procedural generation for the palaces. Hoping they do something like that for 6.