Who did Jesus really die for?

It can't be non-Jews, because the God of Israel already had a much easier way for them to have a place in the world to come, and it didn't require sacrifices or even belief in him. It wasn't for Jews, because they never needed salvation either, since they don't have a concept of Hell and they were able to atone for their own transgressions (and horror of horrors, they atoned with the person that they wronged as well, not just with God). So, since neither Jews nor non-Jews needed a savior, who exactly did Jesus die for, and why?