I think that the first line "watching cars....it's gone" is a metaphor for the next line "heros die...never stay". A hero that dies off is a father that leaves, because a father figure is suppose to be a hero figure, and when fathers leave, it's the same as a hero dying off. But sometimes kids can't accept the reality."hopeless opinions" probably refers to hopeless thoughts of getting their hero back. And that being all that he has learned is saying like learning a huge life lesson from acknowledging this reality.
I think that the first line "watching cars....it's gone" is a metaphor for the next line "heros die...never stay". A hero that dies off is a father that leaves, because a father figure is suppose to be a hero figure, and when fathers leave, it's the same as a hero dying off. But sometimes kids can't accept the reality."hopeless opinions" probably refers to hopeless thoughts of getting their hero back. And that being all that he has learned is saying like learning a huge life lesson from acknowledging this reality.