Not quite. I’m not assuming such reasons either do or should exist. The question of moral realism begins with Plato’s thought experiment and then seeks to find out if such reasons exist. The anti realist will answer in the negative, such as you have in your comments. The realist answers in the affirmative. The claim that there’s no evidence for moral realism is simply false, and I’d be happy to point you in the direction of the best literature on such evidence.
However, the point of this article was to argue that evolutionary considerations like those of Ruse simply don’t give us any good reason to doubt the truth of moral realism.
Of course nothing in this post should be taken as an attempt to show that moral realism is true either. A defense of that is something one would find elsewhere.
At this point you and I are basically talking past one another by merely asserting our views on ethics. I’m more than happy to engage in a substantive defense of moral realism if you’d like, or a defense of any specific claims I’ve made in this post that you disagree with.