I could write and essay about this, but largely I look at the individual parts when comparing, and some context needs to be applied.
Disney is attempting to adapt something that takes place mostly in the real world and IMO a lot of the flack thrown at Disney is because "the things are what they are"...in other words the warehouses are *supposed* to be warehouses, and the borderline brutalist buildings are *supposed* to be cold and industrial...However, I can't blame people for taking a look at it and going "meh"...
Universal's version on the other hand is bringing out the glossy, neon, bolder characteristics of being in a comic book. It's rather charming and has a lot of heart and character. Buuut could be viewed as somewhat kitsch and budget cutty by some.
I find Universal's far more dynamic and interesting...but I'm also an IOA-simp and it's one of the few things at Universal that hasn't changed all that much since it opened
The best way I know how to explain it is Universal's Marvel is Sam Raimi's Spiderman and Disney's Marvel is Holland Trilogy
One is clean, modern and hits the right beats. And the other one had character, heart, and you're guaranteed to watch it whenever its on
I also argue without Spiderman as the anchor to Universal's Marvel it might not be viewed quite so fondly
Also, Disney's food offerings are much better in their Marvel land, as are the character interactions.