A few people have asked if the LDS consider polygamy immoral and I’ll try to answer.
LDS still consider D&C 132 to be a canonized revelation from God which means that “plural marriage” is not immoral or a sin IF (and ONLY IF) it is authorized by God though his prophet.
38 David also received many wives and concubines, and also Solomon and Moses my servants, as also many others of my servants, from the beginning of creation until this time; and in nothing did they sin save in those things which they received not of me.
39 David’s wives and concubines were given unto him of me, by the hand of Nathan, my servant, and others of the prophets who had the keys of this power; and in none of these things did he sin against me save in the case of Uriah and his wife; and, therefore he hath fallen from his exaltation, and received his portion; and he shall not inherit them out of the world, for I gave them unto another, saith the Lord.
(Doctrine and Covenants | Section 132:38 - 39)
However, we also believe in “honoring and sustaining the law” as proclaimed in Article of Faith #12. I believe it is for that reason that OFFICIAL DECLARATION 1 and 2 were issued in 1890 prohibiting the continued practice of plural marriage, which put the church in harmony with the laws in the United States.
But even if polygamy became legal in the United States I don’t believe the church will ever practice it again. I believe it served a purpose for a relatively short period of time in the early days of the church and that purpose was fulfilled. Of course, we believe in a living prophet so anything is possible but I personally don’t think it’s in the program.