(I realize the irony in my typing this, that I appear to be saying Weinstein was responsible for something a number of people would argue a woman started, but hey. That's not what I'm saying, and you get my point and what I'm trying to say.)
Put another way, Susan didn't go after a high-profile leader directly. She went after systemic issues in a company. Weinstein, on the other hand, showed a lot of people that high-profile leaders are vulnerable to public attention, and that became a slightly different species of snowball. Both are cultural contributions.