Sun and Moon were amazing in everything but gameplay. Amazing setting, amazing music, amazing characters, objectively the best Pokegirls in the franchise so far, even some really good new Pokemon like Ribombee, Golisopod and Mimikyu, but the gameplay was way too railroaded, unskippable cutscenes up the ass which kills replayability and the concept of the Ultra Beasts was severely undercooked, and USUM did almost nothing to fix those issues. I have always said that SM was a beta version of a Pokemon game, while USUM never left early access.

On the topic of Ultra Beasts, it's criminal how barebones the entire concept was, the Ultra Dimensions were nothing but glorified hallways and the URS is remembered by almost no one to this day.