I think it's easy to focus on the thing you disagree with. Like, I'm not sure how to vocalize this. Think like, a pessimistic viewpoint on something that isn't
that big but it can seem that way. (?)
As you just said, we've got jazz and other genres. But off the top of my head, the rock from this whole expansion comes from the main battle theme, the main theme, the mid boss music, The Twinning, and the first half of Ruby. That's off the top of my head. Versus everything else that actually isn't rock. Titania was not rock, nor Innocence, nor Hades (first half was hype thematic but second is the REAL theme), and YoRHa is all Automata. I don't have the OST list in front of me to double check, but this feels like having a biased perspective because the overall OST is so different from what OP would like.
Not to say OP is wrong for wanting it, but it really feels like Heavensward was the OST for what he was looking for but this expansion is focused more on out of this world bangers.
This guy breaks down Eden Refulgence theme, and man- there's so many layers that I think Soken is just inventing genres at this point.
https://www.youtube.com/watch?v=Sr2TBQNOeCg