system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why aren't polygamist rights treated similarly to gay rights?

Alright, I'll first start this off saying I am a supporter of equality for the LGBT community and support the legalization and recognition of gay rights.

So, I was wondering, why isn't polygamy given the same treatment, where people should be free to multiply marry if they would like to. I'm guessing it is because of the sexist, usually male-centric, and cult-religious association to polygamy, but if it allowed a woman to have multiple husbands, or for homosexual/mixed polygamic relationships (5 guys, or 5 chicks, or 3 dudes and 3 chicks, for example), then why isn't the issue given similar treatment.
gpt
Polygamy is a far more complicated change - to make polygamy work, you have to rewrite every law about what a marriage is, what the rights connected to it are, and so on.

For example, if A, B and C are all married to each other, what happens when they divorce? Does each get 1/3 of the household income paid to them in alimony? What if C wants to divorce B but stay with A? What if C wants to marry D as well as A and B, but B doesn't want to marry D?

Who gets the visitation rights in hospital? Or healthcare benefits? Or child custody? How do you tax them?

With gay marriage, all you're doing is changing the list of people who can get married, you're not changing the nature of the legal relationship as you would if you add more than two parties.

Note, that doesn't mean that we _shouldn't_ do it, or that it's morally wrong or right to have polygamous marriage, only that it's not the same as allowing gay marriage and it's much harder to actually implement the changes.