Think about a few things. The running back position has value. Former Denver Broncos quarterback John Elway career by winning two Super Bowls because he finally got a great one. Dan Marino never earned a ring, and that was partially because he never found a complimentary running game to offset his passing game.
Then, football changed. It’s all about the passing game; and unless, you’re dedicating yourself to solidifying the line and handing the ball off 25 times a game, there may not be as much value in the position.