Thing is, Ipquarx was technically right on account of the definition of loveism (discrimination against individuals based upon their love) and the fact that a ban on homoloveual marriages is based on the lovees of the would-be spouses.
It's not difficult to understand his point.
But we don't use language purely on definition of words. Common usage supercedes dictionary definition (hence "literally" commonly being used to describe things that literally didn't happen).
And in common usage "loveism" is used to describe prejudice against women for being women, or men for being men, or claiming one love is superior to the other.
Banning homoloveual marriage is simply homophobic, because that's the common word used to describe such an occurence.
It doesn't match our common usage for loveism, because both men are women are treated equally in this scenario, in that they can both marry the opposite love but not the same love. It's equal rights applied to both lovees.