Marriage was initiated by God. He established it by Himself. So, whatever we want to know or do about marriage must be according to the standard God set. We cannot use our own mentality or reasoning to establish another type of marriage. We must make the marriage the way God started it.
When God created Adam, He made for Him one wife, Eve. There were not many wives. So, having more than one wife or one husband is not according to God's plan. That is the desire of man.
When we refuse to follow the rules of God, he will give us over to our own ways. The Lord Jesus Christ answered the Jews that marrying many wives or many husbands was not God's purpose from the beginning. This answers the question about polygamy. God is not pleased with polygamy.