[masklinn]

The rarity of such events (as outlined by TFA) is probably a major reason, even more so as they seem to generally be caused more by maintenance and from places with less than stellar incident reporting.

While there is some amount of proactivity in aircraft safety I'm not sure there are people with enough free time that they can make up failure modes or trawl through every minor incident report until (again as in the case of TFA) prompted by an actual failure, unless one of the minor incidents is itself proactively raised as a major risk avoided by blind luck.