I think that oftentimes people take offense to these type of compliments when it’s not something that they like about themselves. They don’t want to be identified by that feature, period. If you’re a dark skinned woman and you’re insecure about your skin tone, even in compliment form the person is still letting you know that you’re dark. It’s like, “you’re dark... I like it though”. They’re always either being told that they’re dark and ugly, or dark chocolate sexy, but always a constant reminder that they’re dark, unusual, other.
Sorts OT...
My co-worker has a thing for noses. Particularly certain African/ethnic noses. She is always complimenting someone on their “beautiful nose”. I can always tell who doesn’t like their nose. They look/act like they’ve just been exposed. Last week somebody was about to cuss her out. Lol