It's always blown my mind that pass blocking can keep a elite talent off the field. The type fo back that ends up at ND, or any other big time program, almost always has ridiculous physical traits - size, speed, strength, athleticism, or some combination of the 4. It's a requirement for the job. Sure, some are undersized, but that really doesnt even matte - some of the smallest backs have been the best pass blockers, i.e., Kyren Williams
Most of the time, it's really not that difficult of a block. You're not being asked to pass set an edge rusher 1 on 1 and sustain the block on a 5 step drop. Usually, you're stepping up into the pocket and putting a hit on a blitzing LBer or helping out a lineman who gets beat. The pass-pro responsibilities for a back usually aren't that complicated either. Most of the time, you're scanning inside to out and hitting the first guy who comes through the line.
If you're physically capable of carrying the ball at this level and know the offense well enough to run it, you should have zero issues learning to pass block. It's almost always a matter of wanting to do it.
This rant has absolutely nothing to do with the freshman backs on the roster. It's just me screaming into the sky.