People need to keep in mind that as an author he would almost certainly have to carry his own insurance. Now, it is possible to get group rates from groups like the National Association of the Self-Employed (I've done it in the past), but the coverage is expensive and isn't too good.
As a relatively successful author (I assume, and I have one of his books), he is probably a lot better off then some of the self- or non-employed, and perhaps he had under-insured himself, perhaps because he couldn't afford it, perhaps for some other reason.
Even if he under-insured purposefully (and in retrospect, by mistake -- remember, "hindsight is..." and all), that's no reason for people to think he deserves physical and financial ruin. After all, it's easy to be right and a hater by saying "you made a mistake." It's harder to be right and compassionate by saying "yep, you made a mistake; let's see what we can do to rectify the situation."