No, losing to the Hulk doesnt make you goblin level. However people dismiss him as easily as if he were a street level enemy. Magneto ought to be able to stop the Hulk with little effort. Now I'd be more hesitant to give him a win against someone like Superman in their first encounter. But in a rematch, once he has a chance to better plan for his enemy, I think he could potentially beat Supes.
My question is, why couldnt Magneto create bubbles in people's heads and what not similiar to Invisible Woman? If he can create fields to shield himself, levitate or capture others, why not use them in the same fashion?
Also a HF wouldnt mean anything to Magneto. Generally if he wants you dead, he kills you, not wounds you.
It's his chosen way of leaving a "Magneto Was Here" post-it.
He was born into a world where sapiens love making weapons out of iron to shoot at him. Its not surprising he likes to use the very substance used to threaten him and his people to strike back at his aggressors.
Magneto could just as easily spontaneously combust superpeople by ripping apart hydrocarbon chains in their skeletal structure to produce distinct hydrogen and oxygen ions.