>>115585130Okay, I can understand that stance. But you have to remember that Steven Universe wasn't JUST a serious story-driven cartoon. It could also be a humble slice-of-life comedy one episode and a romance drama in the next. The show covered multiple different genres throughout its run.
You should also keep in mind that Motorcity was produced by Disney, a company that has endless billions to throw at its projects. Avatar itself was a miracle that somehow earned Nickelodeon's support, and Mystery Inc. was a WB Animation production (which tend to have bigger budgets than CN Studios productions, if Looney Tunes Cartoons and DCSHG are of any indication).
Steven Universe was like Adventure Time in that you never really knew what kind of episode you'd be tuning into, and its art style allowed that variety to flourish. Also, I'm pretty sure SU's budget was similar to WBB's, only the Crewniverse went above and beyond to make their show look as ambitious as possible, down to the finer details and subtle hints of an ongoing timeline in the backgrounds and wardrobe changes.
TL;DR: Steven Universe wasn't just a serious cartoon, and it looked perfectly fine.