Why Is James Dean Revered?

From Judas Priest’s song, Heroes End:

I saw on silver screen an actor’s rise to fame
But fast car user lose
That legend’s born from death and that is such a shame
'cos every year new ones appear

Why do you have to die to be a hero
It’s a shame a legend begins at its end
Why do you have to die if you’re a hero
When there’s still so many things to say unsaid.

(The song also references a female singer and a guitarist who I assume must be Janis Joplin and Jimi Hendrix.)

It’s also interesting to note the suspicious presence of the letter J in tragic celebrity deaths.