If it's a NRSA standby, getting an E+ seat if they are still available is quite literally part of their NRSA benefit. Good luck finding a UA employee, who that is part of their benefits, to make the decision to remove getting the best seat still available when clearing NRSA. Not to mention, good luck getting GAs to actually enforce that when it would directly impact them, and their colleagues when they're flying standby. Plus the majority of cases it is not the gate agent manually going through and putting each standby in the seat, it is an automated process that runs at a certain time prior to departure, and can be manually triggered to clear standbys into open seats. That process prioritizes giving the best seats still available depending on the standby code being used.

Eons ago, airlines including UA used to provide meals on every flight, fly planes at 30% capacity, have every row with seat pitch equivalent to today's E+, etc. Know where all those policies got the airlines? Bankruptcy. So maybe policies they had eons ago weren't the best thing for the airlines and are eliminated for a reason. What you're proposing is they give premium customers in coach two seats for the price of one. This is the same attitude as people who think the airlines shouldn't so aggressively sell their FC seats so they can get their free upgrade from coach. And the response to that is the same, if you want an extra seat empty next to you, there is an option to pay for that, but expecting the airline to set it aside just because you're flying in coach, which is what you paid for, is a bit of a stretch. Just like WFBF, want an extra seat, buy an extra seat.