If the only way to secure ivf was to enact laws which state that a person can murder someone else because they called them a racial epithet or used the wrong pronouns, would you still say we should support it?
It’s the same thing. For goyim, abortion is 100% murder that they are chayav misa for.
If you’re really concerned with being able to keep the mitzva of pru urvu, and you’re not motivated by political bias and “big orange man is bad,” then you’ll see that you can’t sacrifice one mitzva to do another. We cannot support goyim doing aveiros vis a vis the 7 mitzvos of bnei noach, as they are obligated to make courts which enforce the other 6(see minchas chinuch on parshas noach, i believe it’s there).
We say in davening every day that the world should be fixed bmalchus Shakai, in the kingship of Hashem, through the keeping of His laws. We cannot support someone He is against, whether that makes us theocrats or not – we have a higher authority to answer to, one who will not care what your political philosophies are, except for that which is either in sync with, or opposed to, His divine will.