I hope that what he meant that Hashem didn’t design them for it , and gave them talents that men don’t have for other areas.
I can live with that. It is like comparative advantage, even when one party is better at both things, it makes sense for one party to do one and the other the other.
If so, I retract the dummy comment. But since I haven’t been able to find the Rashi (help?), so I don’t know what he really said.