This shit always comes up on /co/, so let me break it down for you fags.
Sometime after Walt died peoples art styles peaked, most people who had great art styles went to work at Warner or Disney. However, Disney being pioneers of the industry, kept looking for newer things to start and latch onto. So, in the 70's and 80's they spent their time making CGI look good, they realized CGI was a much cheaper, way better, and smoother way of animating new shit and new movies because why hire 200 animators to draw individual cells when you could hire 20 people to rig skeletons to models and animate the shorts/movies?
However, the first instance of the path of 2d and 3d animation diverging was in 1995, when Toy Story released. People realized that Cgi animating was a legitimate way of animating and was cheap and could get really REALLY good results in general. So, american animators went more towards investing in 3D animation because it was cheaper and looked nice. While we went full force into CGI, Japan and other countries went full force into 2D animating. Because Japan was looking for things that looked nicer, not really cheaper. The animation also changed in Japan drastically.
This drastic change can be seen in Initial D, when the 3D sections hit, they look like garbage. But this was only 3 years after Toy Story aired! So what happened? Well, it's simply that we invested less in 2D animating and went to the cheaper alternative, while japan stayed 2D animating, and strayed away from 3D animations. That's why our CGI movies look fucking amazing in 2018, but Japans 3D animation looks weird and out of place but their 2D animation looks phenomenal while we have Muh Cal Arts.