Not about change. Flaws are flaws no matter how endearing they are, because you could say all together that's what they are for. It's to engage the viewer into the character. Sometimes for stories and sometimes for humor. When flaws are overcome, that is character development like you said. Dento didn't *technically* one could argue though.
Dento has flaws, but he has not developed from them. But that's ok because he is a fun, energetic character. He doesn't need to in order to be enjoyable.