Churches lost all arguments on gay relationships
"Garbage in, garbage out" is a decades-old axiom in computer science, describing how, when computers are fed nonsense input, they will dutifully spew out nonsense output.
It also applies to religion; a logical construct based on false premises, such as a moral arbiter, God, inevitably comes to erroneous conclusions, such as homosexuality being a choice, or that marriage can only be between men and women.
So we are seeing in the fallout of the Irish marriage referendum. This result is a huge milestone in the progression of society towards pluralist secularism and away from theocracy.
The Catholic conservatives blame the Church for having shifted away from its core principles (the "garbage in"), causing people to change their attitudes away from homophobia (the "garbage out") and become not just accepting, but enthusiastic for same-sex marriage. It is the adherence to these core principles that drove people away in the first place.
The Churches have lost the factual arguments (biology tells us sexual orientation is not a choice and history tells us marriage has changed constantly) and, consequently, are losing the moral ones.