They also invented the sewing machine and the industrialization of that and put lots of women out of work. And then they got more office jobs I guess. And it also liberated men from not needing a women to wash/clean/cook. So men shoot themself in the foot some what with that. Wouldnt be surprised if some of these women out of work then became female rights activists. In earlier times they probably got appreciated a lot more if they could sew clothes and didnt just had to spread their legs and cook/clean.