Hair, water, and wind - its crazy how those elements are the things that continue to have levels of improvement for these animated films yet for my eyes i keep thinking "well thats looks pretty solid to me" only to be outdone by the next movie and go "oh yeah that looks better somehow".
I totally agree. I love watching a small set of animated films over the holidays in time order to really see the technical progress. It's especially fun to go from something nostalgic I loved as a kid, to something I can really see the technical underpinnings of today.
Learning about these improvements gives incredible respect and appreciation for our eyes evolved over millennia.
Try watching the first Shrek movie to see how far we've progressed!
It helps looking at CGI with a known reference point, like human characters. Every flaw is much more visible than in a "cartoon" like Zootopia.
It doesn’t seem to matter much for my enjoyment of the films though. Makes you wonder why we are investing in it.