This seems more a case of "some people are idiots". I certainly didn't grow up with Chinese culture, but the idea of a child growing up and leaving home is universal. It didn't make me cry the way some pixar stuff does, but I thought it worked wonderfully.
Also, how does that work thematically when those characters are already there? Maybe they realised they messed up by not including a M&G?
It doesn't work thematically. Current day Disney doesn't care though