But neither is your skin colour expressed in Latin. It becomes a slur based on how and when it’s used.
I agree with feeling ‘obese’ is a neutral, objective term for the physical/medical fact. But then, coming from a non-Anerican context, I used to have no sense of the N word being so offensive, any more than any other random insulting (or even affectionate!) term.
In the wrong context, ‘obese’ can certainly be hurtful and inappropriate. I can imagine, for some people, it’s a trigger word of years of pain and mockery.