Why is there literally NO evidence?

I will start with I want to believe. I was always fascinated by UFO/UAP phenomena and when Grusch came out from the curtains I had an euphoric feeling that something will finally break and other high ranked officials will come out of the shadows as well.

But none of that happened. No exact evidence. If this conspiracy is as big as a lot of people here is saying, then some leakage of evidence would have to occur in such a long time of modern history. No govt is able to contain this. There is 8 billion people on this planet and if there was something to see or something that is bending our understanding of physics/science/chemisty, you name it, then it would take exactly one person to come out with exact evidence. Some hacker group, official on a death bed, crazy motherfucker with nothing to lose etc.

So my take is no one knows a thing. No one is witholding the secrets of free energy, no one is holding the most advanced alien technology and definitely no one is concealing the aliens from the public. Maybe some hints, but definitely not the whole image.