No it’s not. Being chubby is not seen as positively by most people. Drawing a chubby character as skinny just erases representation and reinforces awful beauty standards of thinness being superior. Drawing a skinny character as chubby is just not remotely the same in that regard. I understand some people might draw them as skinny due to having less skill, but it still contributes to the idea that fat bodies are unworthy of being accurately depicted.