The idea of polygamy did not come from the mind of God but the desires of men (males).
Gen 16:2-3
(2) And Sarai said unto Abram, Behold now, the LORD hath restrained me from bearing: I pray thee, go in unto my maid; it may be that I may obtain children by her. And Abram hearkened to the voice of Sarai.
(3) And Sarai Abram's wife took Hagar her maid the Egyptian, after Abram had dwelt ten years in the land of Canaan, and gave her to her husband Abram to be his wife.
Gen 30:1-3
(1) And when Rachel saw that she bare Jacob no children, Rachel envied her sister; and said unto Jacob, Give me children, or else I die.
(2) And Jacob's anger was kindled against Rachel: and he said, Am I in God's stead, who hath withheld from thee the fruit of the womb?
(3) And she said, Behold my maid Bilhah, go in unto her; and she shall bear upon my knees, that I may also have children by her.
Gen 30:8-10
(8) And Rachel said, With great wrestlings have I wrestled with my sister, and I have prevailed: and she called his name Naphtali.
(9) When Leah saw that she had left bearing, she took Zilpah her maid, and gave her Jacob to wife.
(10) And Zilpah Leah's maid bare Jacob a son.
Gen 3:4-6
(4) And the serpent said unto the woman, Ye shall not surely die:
(5) For God doth know that in the day ye eat thereof, then your eyes shall be opened, and ye shall be as gods, knowing good and evil.
(6) And when the woman saw that the tree was good for food, and that it was pleasant to the eyes, and a tree to be desired to make one wise, she took of the fruit thereof, and did eat, and gave also unto her husband with her; and he did eat.
I contend that.... the father of lies manipulated circumstances that mankind might be overcome through the subtlety of the serpent.... This hasn't stopped, even to this day. That's why I said in another post #69:
Please don't forget, "There was war in heaven: Michael and his angels fought against the dragon; and the dragon fought and his angels." There are spiritual adversaries continually working past and present to destroy the Almighty's salvation plan for mankind (Eph 6:12). Blinded men participate in bringing about the adversaries schemes (1Co 2:8).
Forasmuch then as the children are partakers of flesh and blood, he also himself likewise took part of the same; that through death he might destroy him that had the power of death, that is, the devil;
1Jn 3:7-8
(7) Little children, let no man deceive you: he that does righteousness is righteous, even as he is righteous.
(8) He that commits sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil.
I don't think it was God's desire that men should be destroyed, and neither his desire that men should be subjected to eternal damnation. But I believe the scriptures do point to it being his desire that men should overcome the works of the devil and his angels, the roots and branches of which shall be destroyed out of the earth (Rev 12:9) forever in due time.
Mal 4:1
For, behold, the day comes, that shall burn as an oven; and all the proud, yea, and all that do wickedly, shall be stubble: and the day that comes shall burn them up, saith the LORD of hosts, that it shall leave them neither root nor branch.