There is clear evidence that the D&C 132 revelation on polygamy was manufactured by Brigham Young and was not written by Joseph Smith. The LDS church teaches that Joseph wrote it and practiced it and lied about it and hid it. There are plenty of videos debunking the LDS claim of which here are a few:
Karen Hyatt: https://youtu.be/bLbLQR95zj8?si=k-2P9fF3Sv3KIblc
Connor Boyack: https://youtu.be/p-7q2N2HefY?si=oEvL1Mqb80GJoTzs
Rob Fotheringham: https://youtu.be/r57oPlOgY6w?si=Pb0xihhRqXpscaf2
Jeremy Hoop: https://youtu.be/bnVKijsYLHE?si=9Q2wW3qb31koxjXs
With that out of the way - I want to argue that according to the teachings of the Church via D&C 132 - pornography is perfectly acceptable if you feel the Lord has sectioned it for you. Let's see how I get there.
Webster's 1828 Dictionary
Concubine
CONCUBINE, noun [Latin , to lie together, to lie down.]
1. A woman who cohabits with a man, without the authority of a legal marriage; a woman kept for lewd purposes; a kept mistress.
A concubine is kept for sexual purposes. D&C 132 accepts the use of concubines if the Lord gives them to you.
37 Abraham received concubines, and they bore him children; and it was accounted unto him for righteousness, because they were given unto him, and he abode in my law; as Isaac also and Jacob did none other things than that which they were commanded; and because they did none other things than that which they were commanded, they have entered into their exaltation, according to the promises, and sit upon thrones, and are not angels but are gods.
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.
If you are a man who feels that the Lord has given you multiple sexual partners (aka concubines), according to the LDS church as found in D&C 132, this is perfectly acceptable.
And let's say you were deceived by that "prompting" telling you that the Lord wanted you to take on more sexual partners...D&C 132:26 accounts for that and assures you that, well... you'll be okay in the end. Verse 26 says that if a man marries a wife and they are sealed by the Holy Spirit of promise and they go on to commit ANY sin or transgression and if they do all manner of blasphemies AND as long as they don't murder - they're still fine - they will still come forth in the first resurrection and enter into their exaltation. Yes, they may have some trials until the day of redemption but in the end they will still be exalted.26 Verily, verily, I say unto you, if a man marry a wife according to my word, and they are sealed by the Holy Spirit of promise, according to mine appointment, and he or she shall commit any sin or transgression of the new and everlasting covenant whatever, and all manner of blasphemies, and if they commit no murder wherein they shed innocent blood, yet they shall come forth in the first resurrection, and enter into their exaltation; but they shall be destroyed in the flesh, and shall be delivered unto the buffetings of Satan unto the day of redemption, saith the Lord God.
I'm not advocating for this. But I am saying that the LDS church's own narrative provides justification for multiple sexual partners.