I think that you are taking things a bit too far in your zeal to fight this teaching.
No it doesn’t.
1Now the Spirit expressly states that in later times some will abandon the faith to follow deceitful spirits and the teachings of demons, 2influenced by the hypocrisy of liars, whose consciences are seared with a hot iron.
3They will prohibit marriage……
It says that some will, not anyone who does. Otherwise marriage to your sister would qualify as a demonic teaching.
But I agree that teaching against polygyny is of the enemy.
Overstated, they could have still prohibited it without needing this misunderstanding. In fact, (as has been already discussed ) no marriage in which a man desires his woman could take place if the strict meaning of the verse is observed.
He is condemned in his own heart, but he is not guilty before the Father.