I'm not so certain that it was the running backs.
If you remove the running of mobile QB Bryce Perkins , nobody ran well because nobody blocked exceptionally well on runs.
Hmm, let me restate. there was typically one or more offensive linemen who really didn't block well on running plays. I'd give the offensive line a chance to regroup and reset before I'd sound the alarm. Some guys blocked really well. I saw a couple plays where Bobby Evans did not look good at right guard. Not good at all.
But yeah, if the Rams make a move, there will be plenty of talented bigger bodies to claim off waivers, even as early as August 17, when all teams must trim their roster size by 5 and get to 85.