I would offer a different angle to use when looking at this. Theme is about experience. Meaning, it should arise organically. You can make a statement, try to justify, etc. as much as you want. It's about how a person experiences the land. Pretend someone who speaks no English at all walks around the park. Would they say "animals" or something different? Would they be able to identify the themes? And, at what depth? And, how much does it make (or doesn't make) sense? I don't think "animals" is the theme most see nearly as much as nature, wildlife, exploring a natural world/place, etc.
That is obviously a very personal thing, but that's the litmus test. I would argue Zootopia falls into the same category as Chester and Hester's. It doesn't fit the feel or ascetic of the rest of the park. While "fun", it sticks out. That means it's shallow theme. And, that's fine if that's your intended audience. But, there is a material portion of the Disney Parks fan base who grew up with something deeper and want that. That's part of the "magic".
Epcot and DAK (and formerly DHS) had strong overarching themes. MK, while looser as all Castle parks, had the concept of "lands" which themselves had strong overarching themes. These moves are about popular characters with loose ties, not theme.
I can move the modern Starbucks from Disney Springs next to Geyser Point at Wilderness Lodge under the "theme" of the Pacific Northwest. Some will love it. I'd argue it would cheapen the resort's theme significantly, and I don't think I'm alone in that.