Yeah, when you compare American animation to anything else done in North America, you can say, "B-but Steven Universe is pretty ambitious!".
When you compare that to stuff from Europe and Japan, suddenly the bar falls.
When you compare it to actual live-action works, suddenly something like Roseanne comes across as fucking Emmy-award-winning when put up against "ambitious" American toons. The fact is, the majority of animation seems to lack a lot of basic storytelling elements which is why it's viewed so pitifully by other people.
They excuse it because "it's for kids!" even though children's literature is far more ambitious and sometimes even better written.
People who watch live-action never take it seriously unless it's South Park because let's face it, we don't even have a single show worthy of comparing to something viewed highly like Breaking Bad.
We grade our things our a curve because of how low the standard is for animation. It's why shit like Space Jam is viewed as a "pretty good kids film" because what the fuck else are they gonna watch? Who cares if it's a good film, it's a good film ~for kids~!
It's bad enough we have small studios trying to take advantage of the kiddy market by making crap like The Nut Job, but when artists like Gennedy and Rebecca Sugar think they're somehow progressing the medium even though their stories are simplistic, cliche, and often riddled with pacing issues, you start to realize that these aren't artists passionate about their medium, they're people who literally can't hack it in the live action industry.
Just look at the amount of Pixar directors who tried to make a live-action movie, failed, and had to come back to animation. Brad Bird being one of them. Mike Judge seems to be one of the few who can tell a good story regardless of medium and can jump back and forth between the two without an issue.