Well, Bob Dylan is still fairly popular.
Maybe that's why he got it?
The problem with looking at past cultural award winners, Nobels, Oscars, Man Booker, etc is that the awards are a product of the moment and there is no way to know how the book/movie/whatever will hold up over time. (If that is even a consideration.) One decade's "daring trendsetter" might be the next's unreadable/unwatchable bore. Or an author deemed trivial might prove enduring and historically important.
The times, they keep on a-changing.