Let’s say a man is working with a woman in a professional capacity. Let’s further say that, without necessarily wanting to pursue a romantic, sexual or any other sort of personal relationship with her, the man finds the woman physically attractive. It’s hard, after all, not to notice when someone else is attractive.
Seems to me that the man in question really ought to keep his opinion to himself, at minimum until and unless he has established a strong level of rapport and mutual professional esteem with the woman in question. And maybe not even then. This isn’t so hard, is it?