Actually, it’s not all that surprising when a female writer pens an anti-feminist tale.
Consider the Twilight series. That was profoundly anti-feminist, and it was written by a woman. The simple fact is that many women don’t enjoy the demands of feminism and would rather throw in with traditional feminine sex roles.
In the case of Rumiko Takahashi’s Fire Tripper, I think the writer simply wasn’t feeling thrilled with modernity.