If there is not a cloud in the sky and the sun is shining, I wouldn't need to state that as a matter of opinion. I would have no need to frame it as, "I *believe* that there is not a cloud in the sky and that the sun is shining", even though I would be stating my belief. Reality is what it is.
It is disturbing that the definition of marriage (man and woman) is being framed as a religious belief, which has a connotation of being merely a deeply-held opinion or conviction, but not necessarily the truth.
Radicalize and demonize the opinion, and the believers of said "opinion" can be banished from the public square or worse. The radical opinion (truth) can be run out of town on a rail, pushed by the momentum of a mob of consensus worshipers.
If such things as homosexual marriage and "sex-change" are indeed "fake" or "lies" or are untrue or not real, then there would appear to be no need to deal with them at all. There is no need to address things that don't exist.
In a sane world, that's how it worked. When I was growing up there was no crazy talk about homo marriages or transgenders. But for those who need to create something out of nothing, such as rights that don't exist, they pull stunts like this: