Obviously not. But if you crack RSA, you dont't go bragging about it on social media. If people took it seriously, every intelligence agency and criminal organisation in the world would like up to kidnap him and be the only ones to be able to exploit it for a while, and to keep everyone else from doing the same. I assume this hasn't happened.

It would also be simple to demonstrate the ability without giving away any information about how it was done, which would instantly force the world to react. I assume he neglected to do this.