If every passenger on the plane was well trained on de-planing procedures, had small bags which were placed near their seat (rather than half way across the plane) and were fully able and willing to follow directions and wait their turn, then de-boarding by aisle could potentially have a small increase in speed.
Unfortunately, none of those prerequisites actually exist in the real world. I was a road warrior for work for years, flying nearly every week somewhere. There are a number of frequent flyers who know the ropes, know where to go and how to get their bags in and out of the overhead compartments with the least amount of fuss (and usually have purchased luggage specifically for that) Some types of flights are almost all frequent flyers (early monday mornings, thursday evenings), and can go remarkably fast. But there are always at least a few people who should have known there was no way in hell that oversized bag was going to fit in the overhead, or are so self important that they insist on putting 2 or 3 large bags in the overhead, even if they have to take other people’s bags out to make them fit. When de-planing, there are also always a number of assholes who have important meetings they failed to properly schedule their itinerary around and can’t wait for their turn like everyone else.
Most people don’t get a lot of choice about whether they get an aisle seat or not. They get whatever seat was available when they booked, or nowdays, since the airlines now insist on huge fees to “pick” your seat, they get whatever the airline assigns them. Keeping in mind that frequent flyers usually are the business travelers and consultants who probably only found out where they were going to travel the week before, or could not book the flight “weeks ahead of time” because company policies never allow you to expense things that far in advance. Much less expense the extra costs of “perks” such as picking your seat at booking (noting that many airlines do often allow platinum and diamond level frequent flyers “pick” their seat, including some of the ‘upgrade’ seats with out a charge, which is nice, although it doesn’t really make up much for being away from home every week)
And finally, the airlines cannot get people to politely follow the rules that are there already. There is no way they could ever get all the passengers to follow some more “organized” method of getting off, and on a crowded plane where everyone is trying to grab their bags and get off, there would be no possible way for them to try to enforce it. The “passengers nearest the door exit first” has the advantage in that it’s what is always going to happen anyway.
