Like fine wine...
Only its the viewer that needs to age to appreciate this film. It was captivating. But if you've never experienced watching someone age and die, never had real regrets, never been estranged from a family member, I'm sure you would think it is meaningless drivel, which of course could not be farther from the truth.
So there is nothing wrong with those that don't like it, they just have not yet acquired the taste to appreciate it. It comes with age. The rare teen that likes it has stories to tell I'm sure.
GREAT FILM.