Sure, you could argue that. However, a feature back still is a feared asset for NFL teams. Take Jacksonville for example. While Rashad Jennings and Deji Karim do get carries, the bulk goes to Maurice Jones-Drew. When MJD is in the game, it frees up every other part of the offense.
Legarrette Blount in Tampa Bay is making a name for himself as a future feature back. If the newly-unretired Tiki Barber does come back, it'll likely be at Tampa and his role will be more as a mentor than a multiple-down player.