I meant less that the explanation was obvious and more that it was a very good example of the effect of hindsight bias; hindsight bias produces precisely these kinds of results.

If something else is even more likely to produce this kind of result, then that would be more likely than hindsight bias. I don't think akrasia qualifies.

To elaborate on what I think was actually going on: People 'know' that failure is a possibility, something that happens to other people, and that backups are a good way to prevent it, but don't really believe that it is a thing that can happen to them. After the fact, hindsight bias transforms 'yeah, that's a thing that happens' to 'this could happen to me' retroactively, and they remember knowing/believing it could happen to them.