I can see the number of scanning lanes (which is usually 1) being a bottleneck on large aircrafts with lots of doors, like the A380 example they have given.
I've very rarely seen the case where there isn't a queue after the boarding pass scan and before the boarding door(s) and seating area of the airplane.
This suggests that downstream of the boarding pass scan is already the true bottleneck of the system.
i believe that's why he (and the article) mentioned the A380 which can have something like 4 simultaneous embarking points (probably double that if they board from both sides of the plane).
I’ve only flown the A380 twice. Both times that still had a bottleneck in economy of people getting settled despite boarding through multiple jetways.
The bottleneck is at the seats, esp in coach/economy. On a single-aisle aircraft, this typically backs up onto the jetway, but even multiple door/aisle, the slowest agent can scan tickets and check IDs faster than people can get settled on average even when some of them can settle in parallel (perhaps one per aisle per very few rows).
