I mean, have you seen the other shit they get up to? The FBI doing - or not doing - anything isn't really going to convince me of much.

Although I agree, the FBI actually showing an interest in it is at least somewhat telling. But, again, they also were interested in the aforementioned Steele dossier. But they're also partisan, so it is more meaningful in the case of the diary, as far as authenticity goes. It's kind of a tossup.