So these self-appointed fact checkers... When they can't find any evidence of a claim, they boldly state that the claim is FALSE.
Absence of evidence is not proof that something did not happen. It merely means there's no proofb that it did happen, and that might change over time as more information comes to light.
It would be more honest to simply say there's no proof for the statement, rather than showing big red letters FALSE.
What fact check organisation do you have in mind?
snopes.com and correctiv.org for example do have an "unproven" rating.
politifact.com doesn't seem to have one. I guess there's a reason but I'm too lazy to thoroughly read their about page now.
they do use it. For example:
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