> The strangest thing is that there's a sizable number of women who support the law in its current form.

Different localities have different cultures, and for some, it's good. Say for example, in my locality (Kerala), Muslim men have more than a wife only on certain conditions like:

1. The first wife can't bear a child and the person marries another one without avoiding the earlier wife

2. Marrying widows so as to protect them (there might be occasional cases of exploiting this too, though I'm not aware of any).

I do also have seen a finger countable cases where a man marries some women to threaten other wives. But so far, I remember only two such cases in my neighborhood, and none in my family. Usually such men get really less support from the community.

So women having such an experience shall be supporting the current law.