My issue is that if you dug through all the claims you found the ones OP was talking about and thought "this isn't actually implausible" and if you go a step further and check some sources, it's not for certain but there's enough evidence to be compelling. Yet you would only hear about these things mixed in with the nutty ideas, I guess because it was disreputable to even talk about the government having certain kinds of secrets. Post-Snowden this attitude seems to have been reduced.