Knowing the answer to some of history's biggest mysteries, because you were there, but being unable to speak about them because, 1, that would expose you, 2, nobody would believe you either way because nobody expects you to be THAT old.
IDK, I feel like researching for supporting evidence of a theory you already know is correct would be much easier than researching to try to piece together a theory from no information. I think you could put the truth out there as credible and well-regarded theories, even if there are incorrect alternative theories that people also have to consider.
I once entered an extremely far back yet technically plausible birthday there and steam just wouldn't accept it. I remember thinking "what if Kane Tanaka wanted to check out this steam game, you just wouldn't let her?" (RIP by the way, she was the last oldest person whose name I learned. They change too often)