True, but magic user's rarely do the logical thing and banish characters like strange did to Hulk, simply because it doesn't make a good story. Thor could end half the fights he gets into before they even begin, but he usually goes head up.
Unrelated to the quoted post:
Also, I don't think superman is so much "vulnerable" to magic like he is to kryptonite, it just affects him as it would anyone else; it doesn't sap his strength unless that's the purpose of the spell i'm thinking. You aren't going to be able to hurt him any easier necessarily--for example, Captain Marvel's blows may hurt him more, Marvel's lightning hurts him, and magic blades can harm him because, supposedly, these things bypass superman's "force field"; however, his alien physiology still affords him a great amount of invulnerability--but you can send his ass to another dimension or create some sort of restraint (crimson bands) to hold him. But I think Hulk busted out of those, so you can assume Superman would be able to as well.
