I don't want to paint myself as especially virtuous in a self-serving way, because I can be an asshole like anyone else, but I am not that guy, that particular sexually harassing asshole.
The main reason I don't harass women is that I want them to like and respect me, and, when appropriate, to find me attractive. In my experience, women talk badly about sexually harassing men and do not like them.
In the times when I have not been married or in a relationship, I am not very good at making even appropriate advances. The idea of making an advance that is inappropriate is horrifying to me. My work involves contact with attractive 21-year old women, and harassing them is one of the only ways in which I could lose my job (one of the only ways as a tenured professor). Through no virtue of my own, these women are not particularly attractive to me, since I am an older woman type of guy.
There are a lot of guys like me, I'm sure. There are a lot of reasons not to do it. The main reason, though, is that it is not the way to get women to like you: engaging in behavior that they think is odious.