I agree. This is another example of a very rare event which likely no pre-test of any kind can make a difference in the accident rate. Particularly regarding psychiatric conditions, the sensitivity and specificity of testing for those conditions is just too low.
Indeed, like most regulatory attempts to prevent bad outcomes, a fairly good argument can be made that there are more important unintended negative outcomes. In this case, that the FAA digging around into pilot's medical records may actually increase the accident rate by discouraging pilots from getting needed help.