I don't personally buy that the solution to this is to "rein in the FBI" if we're talking about the security of the CIA chief vis-a-vis the FBI. The point is that a motivated attacker could do all these things to a high value target. It might sound far-fetched but having damaging personal information about a CIA chief is very valuable. I don't condone judging people by their worst actions, but I think that the government would rather the FBI found out this information than someone else.