I'll check out that Joanna Russ book! (Just finished 'How to Suppress Women's Writing' and fangirling her a bit.)

I think there's becoming more tendency to assign clearer roles, but there's a strong history of just the opposite--and I think a lot of bone-deep dislike of it in a lot of places.

That would be a very, very interesting tendency. I'll try and see if I can pick up anything like this from the datasets, although they're probably too limited in time (five years or so).