Can't say I've seen that. I can let hand drawn animated shows slide, because it's a bloody art to do hand drawn animations. It just irks me that they reuse the same models and animations multiple times, yet completely skimp on background texturing and everything else.
I'm not expecting award winning voice acting, animation or post-processing. it just irks me that the ground texture basically looks like something from the early 2000s
It looks like Half-Life textures and environments with Disney Infinity character models to me.
With reference to this example, the plain textures fit the aesthetic but also for young children you don't want the environments to be too busy. As we get older we learn how to subconsciously filter our environment so as to only gather the information we need, children don't have this filter straight away as it is something that is developed over time. This is why kids get so easily distracted but also notice small details that we adults tend to miss. So for kids shows it's better to have simple, bright colours and textures as it is easier for the kids to follow and not get overwhelmed by all the details.
So in many ways it is a budget related thing but there is some intentionality behind the sparse aesthetic. (This is all my opinion, I'm not an expert in the field other than my wife teaches pre-school)
Edit: The shadowing in the pic is pretty decent and there may even be a degree of ambient occlusion![]()