Bob Dylan managed to do it while still being alive, but I think because he was wily enough to learn early on to become totally mysterious and combative with the press.
I think the reason the young are almost always the legends is because they are like insects frozen in amber….hard to see something mythic in some dude with a nuclear family.
I am always really curious about what kind of art Morrison would have made if he wasn’t abusing drugs and alcohol so much. May have been pretty tame in comparison to what he’s legendary for. Can’t say for sure, though.