I strongly believe polygamy should be legalized. Although, this system of marriage always ends up having a lot of challenges, but nevertheless, we are entitled to some rights as human beings. Another thing is, if other types of marriages are being legalized, there is no reason whatsoever for polygamy not to be legalized. I want to discuss from this perspective. The current world's population has a greater percentage of females than what we have for men. Which means, if every man is commanded to get married to one wife, it means, many other women out there won't have the chance to get any husband.
It is for this sake I strongly believe polygamy should be legalized. More so, some religions practiced by people actually support polygamy. In Islam, a man has the right to get married to multiple wives as long as he can take good care of them. And if some religions are supporting this, I think it should be legalized in order to respect their religious right.