Some of us are pretty trustworthy. Some aren’t.
I picked up a great book in the clearance bin. “Founding Myths” about the founding fathers. If you have been educated in the usual way about the American Revolution, this will burst your history believing bubble quite thoroughly. In short, you will look at history and news with great skepticism. Like a historian would.
I trust some historians. I wouldn’t trust any Historians.
Do you trust any psychohistorians? Do you trust any psycho historians?
You can trust historians for the same reason you can trust scientists. The culture LOVES to prove error and the research/results are often concrete.
I trust them to pick facts that suit their narrative and ignore everything else.
I don’t trust any historian who has written a non critical account of any American presidency since Grover Cleveland.
You shouldn’t trust historians any more than you trust scientists. You’re not supposed to believe them on faith. Any historian or scientist who isn’t backing up what they say with evidence doesn’t deserve their title.
Frankly, works and websites like these are amongst the historical works I would be least inclined to trust. That is not to say that their claims are necessarily all wrong, but they do clearly have an axe to grind, and they are using the powerful rhetorical strategy of enticing you to think that you are special because you are being let in on secrets that (so you are told) most people don’t know, and that “the man” does not want you to know. All the ostentatious show they make of revealing other people’s biases is designed to distract you from noticing their own biases. Also, I often find that the “myths” that are being debunked are myths that I (and, I expect, most people) either never heard of at all or never really believed in the first place.
OK, so we here have at least one unreliable historian 
This is threadshitting. The topic is the reliability of historians, not the odd beliefs of people who do not actually grasp history.
Knock it off.
[ /Moderating ]