I don't like the idea of "blaming" his victims for what happened to future victims. In the first place, apparently a few people did try to speak out over the years against him, but they either weren't listened to or weren't taken seriously or the allegations in some other way went nowhere (Rose McGowan being one such, apparently:
http://www.latimes.com/business/la-fi-rose-mcgowan-harvey-weinstein-20171013-story.html ); and then their careers suffered as a result with little to show for it. It's quite risky reporting any crime, especially one that makes you look and feel so vulnerable, and if at the end there might not be anything to show for it *and* you've ruined your career for that lack of result, why would you want to take that risk? Isn't it more reasonable not to bother, and just to get on with things?
Now that it's all out in the open, there's probably also a "herd immunity" too -- people who wouldn't have alone felt able or willing to accuse a powerful man of such crimes or misdeeds can seek solace in the fact that Weinstein can't take *all* of his accusers down.
So no. Blame is absolutely the wrong word to assign to his victims. I regret -- I am sure they regret this even more -- that they didn't come out sooner, and Hollywood as a whole has a lot to answer for that it tolerated something so openly; but I don't blame them for a second for making what may have been the more pragmatic decision to keep silent about their experiences in the interests of furthering their careers.