Legend seems like a movie Scorsese might have made if he wasn’t paying attention - the elements are present but they are clumsily assembled and the outcome underwhelms.
In My point of view To take such a subject and render it without focus, interest, or joy—to make a long, dull movie from it — qualified as some perverse sort of achievement.
However Tom Hardy manages the brilliant trick of playing two physically, emotionally and intellectually distinct mobster brothers in Legend. You can watch once but not neccessary