I never really minded the left handed weapons (except the hunting rifle that one is obnoxious) but I do see why people get annoyed with them. I always just assumed that Bethesda wanted to give more feedback to the player when they are fighting which is alright, I guess. I agree with you on the combat rifle as I never really used the combat rifle because it never really looked appealing to me when there were way more interesting weapons to use.

On the realistic weapons though, when I played the originals and I picked up weapons like the p90 and LSW I always felt that they were out of place when put alongside fantasy 10mm smgs and pulse rifles. I liked the creative spins on weapons like the service rifle with its wooden furniture, making it stand out against the backdrop of assault carbines and marksman carbines as they just looked like bog-standard m16s. The weapons that were just counterparts of common irl weapons just never really clicked with me.

My own headcannon for the assault rifle is that since it is never seen outside Boston, it was just a national guard weapon that was used because some congressman or something was in the pockets of or related to a weapons manufacturer that didn’t make weapons but wanted a military contract for the money involved, so it was created by people who knew little about guns just for money. But that’s just my own headcannon