Hey, here's a group that discusses the history of the Roman and Byzantine state. "...from 753 BC to AD 1475." Oh. No. No, no, no, no. The link to the group shows a picture which they say is of Constantius II's entry into Rome in AD 357. Constantius II did visit Rome in 357. But when was this picture made? I'm guessing 19th or 20th century. I'm also guessing that I could find out more quickly when and by whom the picture was made by researching it myself than by asking the members of the group, and that my asking would probably mostly have the effect of annoying them.
Hey, look at this: Vinča symbols. Never heard of them? Me neither, before yesterday. And yet these people (not the same people as in the previous paragraph) are saying they're a writing system going back to -- 5300 BC? And that there's a bias among academics who study early writing against paying any attention to them? Oh dear. Actual academics simply don't behave that way. They don't cover up plausible discoveries which would "rock the boat." They're boat rockers. The key word there was "plausible."
How many people are there who think that they are geniuses and that their genius is neglected, for every neglected genius? I don't have an actual number for you, but it's a lot.
And Albert Einstein was not a neglected genius: he started publishing papers in the Annalen der Physik, the pre-eminent academic publication on physics at the time, around his 22nd birthday, in 1901, four years before his most famous group of papers were published in the same journal. In 1905, not only were those papers published, but Einstein also received a PhD from the University of Zurich. Although he was working in a patent office at the time, not taking courses at the university or anything like that. He got the Nobel Prize when he was 42 or 43. (He was chosen to receive it in 1921 but it wasn't awarded to him until the next year.) That is not neglect by the academic establishment. That is not by any stretch of the imagination neglect. That is almost as far from being rejected by the academic mainstream as anyone could ever be. Yes, there were people who rejected Einstein's findings, many laypeople outside the field of physics and just a handful within, but they would not have rejected his findings if he hadn't been a rock star within his field. Because they probably never would have heard of him, for one thing, and they would have had no reason to get so upset about his being, in their mistaken opinions, completely, absurdly wrong about space and time and matter and energy. People who are completely, absurdly wrong are a dime a dozen in every walk of life. Someone you think is completely, absurdly wrong, but most of the rest of the world thinks they're a genius -- that's different. That can be very annoying.
I imagine it would be all the more annoying if the annoyed person felt him- or herself to be a neglected genius.
The ones who thought that they were unrecognized geniuses were the ones who vehemently rejected Einstein's ideas. And they weren't geniuses. The geniuses understood Einstein and were blown away. Leading directly to the previously-mentioned condition of him not being neglected in the slightest, but wildly celebrated and one of the two or three most famous people in the world.