The thing is that people keeps seeing Superman as a kind of Goku. A guy whos main plot is to win a fight, to simply defeat the enemy and to show that he can't be defeated. Basically a plot about defending himself.
Superman is not abou that, neither a plot point. His stories are about him protecting his fellow humans, His world.
It's not about resisting his enemies attacks and wining because, you know, he's Superman. It's about the problem of, having all that power that makes him invincible doesn't means at all that he can save everybody.
I liked the monologue in JLA when he said he lives in a world made of paper, or the comic where the atomic bomb blew everyone but him. Yes, he survived the explosion but he could do nothing but bear all his friends deaths. What the fuck matters if he's strong to survive? What matters to him is the safety of everybody else.