Marriage was already comprehensively deconstructed by heterosexuals, long before the homosexuals swarmed in to claim its parts and bits. Through civil marriage, easy divorce/remarriage, and contraception, heteros redefined marriage from being a Natural Law-anchored, fertile exclusive lifelong union, to being a construct of positive "say-so" law, sequentially multipartnered, and sterile.
Marriage --- as obviously defined in all of human history across centuries, continents, and civilizations --- makes sense only as a setting for procreative sex which then defines two-and-only-two people, the male and the female, as the responsible parents. People of random genders rubbing non-procreative body parts together don't require solemn durable societal recognitions, responsibilities or covenants. In such case, there is no need to specify one, two, three, any number of people, and it doesn't matter whether the non-procreative parts are elbows, anuses, noses, knees or reproductively disabled genitals.
Who queered marriage? Heterosexuals. They "redefined" it. It's inevitable that the various kinds of queers would now claim the mutated thing as their own.
No, polygamy has been common throughout history for practical reasons. If a high proportion of men died in war, polygamy both took care of the widows and orphans, and allowed the clan, tribe or whaterever to procrate at the maximum rate.