I'm surprised they didn't go the other way and reduce the men's salaries. They would have cut costs and then issued bonuses all around the board.
That's an interesting thought exercise.
I predict the more qualified would move on, leaving the men who would struggle to get employment elsewhere behind.
If we are to assume the women have the same kind of skill distribution as the men (equal skills) with the same percentage of those skills throughout their ranks, then there would now theoretically be more qualified women in the company than men.
These women could then push for pay raises* as they now stand out as being the best the company has. At which point the men would be (on average) lower salaries than the women. Role reversal.
*I don't think this is the only way it could play out, just thinking out loud. For example, I don't believe women get as many pay raises as men (in general) because they don't push as hard for them. This also applies to the men who aren't daring/confident enough to risk losing their job because they pushed for too much.