You make reasonable points.
For me, however, the purpose of my writing this was not to prove or disprove particular conspiracy theories. I'm more interested in the over-arching concept by itself. Presumably, even if there are people who think a particular example happens to be true, they concede that other examples are false or "wacko". (Though, I know there are studies showing that conspiracy theories tend to clump in specific brains...)
My intention is not so much to lump "people" together, but rather, to lump certain thought processes together.