One could see it as patchy, when you access an airline's website and before you can do anything useful, you have to load scripts that do who knows what, from 20 third party domains, that have nothing to do with you searching or booking a flight. Basically cobbled together slow as molasses ton of scripts, that probably barely work at all.
They aren’t referring to the client side of this question. Airline websites generally have the quality of any generic corporate IT project…
I assume what the parent was referring to is the backend systems like Sabre that coordinates travel and ticketing between airlines, travel agents, etc. It is a truly ancient system by today’s standards, with origins in the 1960s and mainframes. Systems like this actually have started to limit what airlines can do and how many flights they can manage.
Those user-side scripts have nothing to do with booking the flight. The reservation software is running in a data center somewhere, quite possibly on a mainframe they've been trying to retire for 30 years.
