There is a tremendous outpouring of arguments in the public arena, emanating mostly from real Christians, which - taken together - demonstrate that current legislation first to permit, then to enforce, then to impose same sex marriage will (with a very high degree of probability) inflict deep and permanent damage on society.
Yet the legislation proceeds apace.
Simple: because the infliction of deep and permanent damage on society is a feature not a bug of this legislation; it is not an unintended by-product but the actual motivational core of the movement.
The more conclusively harm is proven, the more convinced SSM advocates become that the legislation is desirable.
Thus the more that real Christians argue in the public arena, the worse the consequences - because the more powerfully their arguments encourage and energize the forces of darkness.
Argument is not just futile, but counter-productive.
The only proper response is a clear, plain, simple and uncompromizing statement of refusal - and then courage and endurance to withstand the consequences.
If courage and endurance are lacking, then there is an end of the matter.