To piggyback, in a passing offense like the Rams, RBs and TEs are there to chip block, help with blitzers, and then leak out for check downs. 11 personnel is the conservative end of the "pass heavy" sets. The only more conservative offense you'd see on the Rams is 12 personnel.
22 personnel, 23 personnel are all run-heavy fits that teams like the Rams (and for that matter the Bills) don't often use except in very niche situations. Yeah, conceivably they could have pass-blocked better in those sets, but those are 1-2 WR sets, so your passing game is reduced to short stuff and checkdowns/screens, because with only 1 WR on the field teams can free up safeties to cheat down to the LOS. The Bills actually used a 12 personnel set in the red zone to bait the Rams into exactly that - they pulled everyone left, including both TEs, play actioned the back left, drawing most of the LBs left; then Allen bootlegged right, and they had to play the run on the bootleg, so Jalen Ramsey and another CB bit, and Gabe Davis was wide open for the TD on a floater over the run-playing CBs.
I only mentioned the 11 personnel in the first place because when you're not blitzing, and only rushing 4, with 5 OL and an in-line TE plus an RB in the backfield, you shouldn't get 7 sacks. But the Bills 4 DLmen were bodying the Rams offensive line all day.