My issues with Endwalker IMO are primarily 2 things.
1. We didn't get an exploratory zone and quest line like Eureka/Bozja.
2. The MSQ especially the launch portion of it felt like they were condensing 2 or more full expansion cycles of content into 1 expansion to rush to a story end ASAP.
While there are a number of other things I disliked or had issue with in regards to Endwalker those 2 points are definitely the most prominent.