If we are speaking of magic in the biblical sense, it is wrong and sinful. If we are talking about David Copperfield, it isn't. I have no idea how this became a focus of the discussion.
If one rejects God, they, by default, are playing for the other team. This is clearly explained. There are only two teams to choose from. If one says they are for God, yet engage in things they should not, that person is either willingly sinning or is a liar. Only that person and God knows which. I honestly find it difficult to understand how there is any confusion about these things.
So, if an atheist rejects God, whether he is she knows it or not, they fight on the side of Satan. By loose definition, I would say to the OP, yes. We can "what if" it all day, but to do so seems to question God, the Apostles, the ECF's, Tradition and Scripture. I, for one, am not prepared to question all of that.