Ann Althouse raises the polygamy question.
She and her commenters cover the usual issues; polygamy tends to happen when some men are much richer / more powerful than most men, and it causes friction because of the men left without women. Polygamy is not ruled out by scripture, but by Western Christian tradition. Whether or not polygamy is legal is not a big deal, provided a man can live with a woman and have children without officially marrying her.
What is missed is the real link between polygamy and societies which deny rights to women.
Look at it this way. As we know, it is possible to take a second "wife" without legally marrying her, have children by her, leave property to the children by will, etc. Why don't I do that?
I might have trouble attracting a second "wife", but I fancy I might manage it. It's worth trying, anyway. What's to stop me?
The answer is so overwhelmingly obvious it's surprising it seems to be missed. Were I to enter into any such arrangement, my No. 1 wife would be gone in about thirty seconds.
For polygamy to actually work, there has to be some way to force wives to tolerate the introduction of new wives. If a wife can get a divorce, and a share of property, either for no cause or for the cause of the addition of a second "wife" (whether by legal polygamous marriage or in the form of "adultery"), then polygamy, legal or not, is going to be very damned rare.
Attention seems to be wrongly attached to the new wives. As commenters at Althouse said, there would be nothing strange in a billionaire or a sports star being able to attract a second or third wife. But it would be very unlikely that they could do that and hold on to their first one.
That's why polygamy generally doesn't happen in societies where women have rights.