This isn't really malicious compliance. This is the very foundation of the point made by the Supreme Court. You should be able to refuse service to anyone for any reason. Anything less than that is the government engaging in violence to force you to work.
I don't think it's a smart decision. I think discriminating for any reason makes business sense nor will it win you any allies, but it should be legal. Anything less than that is the government forcing you to work.