Atheism and Ethics

[Angrboda]

That's a semantic question.  From a practical standpoint, an anti-realist makes choices which have a moral dimension situationally.  I don't think it matters whether that dimension is real or not.

Out of interest, is the question of why an anti-realist would act morally just one of curiosity, or does it lean towards evidence against anti-realism for you?

Mere curiosity. I'm wondering how you answer the objection. Given the average person seems, in practice, to be constrained by a conscience, I think that's a significant difference.