Because there are somethings in there, apparently, that neither you, nor I, nor any sane person would want actually declassified. Documents that several entities would sell their mother for such as an assessment of Israel's nuclear forces per one widely circulating DC rumor.
Many people are...
My nephew spent a lot of time in eastern Europe, and thoroughly enjoyed the slender, well-endowed female population, whom the male population referred to as "Tits on a stick".
But he wondered by what infernal process they ultimately all became "Babushkas".
Riiiiight. So you don't like eating fresh fruit or vegetables? Or your hotel room cleaned. Or your boat built. Because you get all of those things through immigrant labor. No pool of workers contributes to the tax base more while taking less from it than immigrant workers.
And, for those...
Yeah, let's make Central Park private. What a spectacularly stupid idea. If private parks are so safe, why are there so many gated communities paying for 24-hour security while my Manhattan apartment right on Central Park just has an unarmed, kind of ancient doorman.
Time and again it has been demonstrated that "intellectually pure" economic systems, whether they are Marxian or Randian, fail when confronted with the real world.
I'm going to go take a walk in a public park.