> [T]hey thought they already had good enough models to avoid taking large losses.
That's a fair point; the essay doesn't do much to distinguish whether they didn't know they needed to take losses, or couldn't take the pain of the losses.
Nevertheless, it's a pretty good analysis of what a company needs to do, in order to build a model relevant to their own actual business. They need to both know about the pain involved, and be prepared to take it. (And even then it might not work!) Third-party data (and suffering) might not be a good substitute.