How the hell did Jackson pull it off?
Over a decade and a half and no fantasy film of any genre has been able to surpass it.
Good source material, a script that respected it in the right places, a number and length of films that wasn't too short to tell the story, nor too long to lead to it dragging on, and a reliance on practical effects if possible and only CGI when absolutely necessary.
He used to be a fat nerd so he paid attention. Then Hollywood got to him and he lost weight...then he made The Hobb*t.