Power dynamics radically changes that. That's why you can't have teacher meddling with their students, or a psychologists in a relationship with their patients.
I can see how it would in some situations. From the article's description though it sounded like a lot of the women at the parties worked in different fields. So, while I fully agree it would be a problem for the CEO to be hitting on interns, as an extreme example, I don't see the power imbalance of a rich guy from one field hitting on a woman in a different field - provided there is no implication of coercion (e.g. it would be a problem if a powerful investor threatened to get a real estate agent fired if she didn't sleep with him, but it's not a problem if a rich investor hooks up with a real estate agent because they like each other for whatever reason, even if his reason is that she's pretty, and hers is that he's rich).