I agree. There is much about history that should be taken with a grain of salt. Indeed, historical perspectives have changed dramatically over the course of the last few decades. In fact, this is a well-discussed topic in college history classes. Historians are always faced with anecdotal accounts and the need to look for what they call primary sources of information.
I'm an archaeologist by study and use "historical" accounts to enhance artifactual finds or provide research questions. But in the end, it is the artifactual evidence that is accepted, not the history if the two diverge. Also, historical accounts are useful if multiple historical accounts can be obtained from independent sources that share different beliefs. Such as in the case of a war or battle: the opposing sides accounts are obviously biased, but the common factors can be accepted as fact. Things like the date, location of the battle, etc. The outcomes of the battles are occasionally suspect, however, particularly when the opposing sides have drastically divergent views.
In the case of UFO believers, multiple sources offer some credibility to the overall account if the common factors can be extrapolated with objectivity. However, the problem with this is that very often the accounts are tainted by bias to believe in the extraterrestrial hypothesis of the UFO (though not always) and/or the so-called "investigator" is using confirmation bias in questions that are frequently leading or biased to investigate the positive while avoiding the negative.