Yes, there are secrets in the world. Many, I'm sure. Now, I believe a man like Napoleon Hill who after many years of study and examination started talking about "a secret". But how many self-advertised secret holders can pride themselves with only a tenth of Hill's effort and knowledge?
I'm not saying that we should all keep quiet unless we had decades of experience behind us. I'm just saying that not everything is a secret, and not everything is ultimate, and, most certainly, not everything is "finally" quick and easy.
And some things are indeed The Ultimate Secret To Quickly and Easily..., but they come only once in a long while and they are a revelation on a sunny morning after years of dedication and passion. I suspect.