With all of the attention airlines give to boarding procedures, often re-working seating zones and procedures in the hopes of boarding people as quickly as possible, why don't airlines also focus on devising procedures for getting people OFF planes asap?

I was in the back of coach on an Airbus 321 recently, and getting off seemed to take forever because:

1. People just sit there playing on their phones, even though if they stood up before it was "their turn" and at least opened the overhead bins, they could save time.

2. Each row at a time goes, even though surely people in aisle seats, without carryon bags in overhead bins, could get off first and clear a lot of the plane quickly.

Maybe disembarking procedures such as the following could save time?

* People in aisles without carry-on bags get off first;
* Every third row gets up and gets their bags and gets off;
(Repeat step 2 until all rows are off)

Perhaps another procedure could be faster, but the issue is that there's got to be a faster procedure than the row-by-row disembarking that is prevalent in the US.