I appreciate the sentiment you were trying to come away from this with: that because of the rapid evolution of technology and the expansion of public access to information from both reputable and disreputable sources, younger generations are having a more and more challenging time discerning what's true and what's not. And I agree; now more than ever media literacy is absolutely vital to understand the world around us and challenge the wild and often unfounded claims of those seeking attention on the internet.
Unfortunately, I think you may well have fallen into one of these traps. The "meme" of not believing in Helen Keller is actually quite cruel when you think about it; to tell people who share her disabilities that it is absolutely impossible that someone like them can be successful is both heartbreaking and demeaning. This is abelism, and it's a frightening stigma that can cause lots of harm to communities that just want the same respect that able-bodied people see on a daily basis. To you, it's a joke; to a DeafBlind person, it's dehumanizing.
You can't choose not to believe in a human being, especially not one whom people still alive today remember having met and seen in person. Helen Keller died in 1968, after having authored several books (which you can find here: https://onlinebooks.library.upenn.edu/webbin/book/lookupname?key=Keller%2c%20Helen%2c%201880%2d1968) and starred in a documentary (which you can watch on YouTube here: https://www.youtube.com/watch?v=8ch_H8pt9M8&feature=youtu.be).
Perhaps, though, you weren't attempting to assert that Helen Keller didn't actually exist. Maybe you were using hyperbole to make a point: that people shouldn't be surprised when things that are commonly accepted as fact are disproven. If this is the case, then you have suffered from very poor wording and an ill-thought-out literary device that is actually causing more harm than good. I recommend removing this article or at the very least rewording it to clarify your intentions.
If, however, you truly believe that a DeafBlind woman can't possible achieve the level of success that Keller did, you need very much to remove this article and reassess your biases. Make an effort to meet some DeafBlind people, such as those that appear in your replies, and to reach out to that community. Connect with people, learn directly from them. That might broaden your interpretation of what a successful person can look like.