Earlier quoted context omitted.
I think his point is more along the lines that regulatory burden and concern for the possible cost of error disincentive for change that effectively borders on paralysis rather than it being a physical reason preventing changes. The same sort of obstacles you see with large companies, but with an extra layer of possible fines on top. A few years back, a designer blogged about a similar redesign for American Airlines.…
Can confirm, redesigns are scary on the money machine. The more cash your engine cranks out, the less likely you will be to experiment. Experiments will fall on low-risk categories, not something as significant as ticket purchase.
Not as scary as how much money your losing because of abandonment.