Fair question. I would say the primary difference is that in most workplaces men are seen as being competent, and being male is not a disadvantage or put you in a minority. There are undoubtedly professions where stereotypes about men would be harmful. For example if a man wants to become a flight attendant, nurse, or a school teacher.
Also consider examples outside of work, like dating. The tall, handsome, muscular guy is more likely to be perceived as desirable even though those traits don't necessarily correlate with what makes a good boyfriend. A man in search of a partner might feel objectified if his potential partner had posters of good-looking men up on her wall.