Whether I personally want it or not, I am convinced that there is a gradual process of disclosure in place and it is happening. Why do I think this? One is example is Apollo astronaut
Edgar Mitchell. I recently read his biography and he pretty well avoided addressing the ET issue. But, he has recently been interviewed and now says UFO exist and there is a government cover up. Other examples - the release of records in Britain, a formal statement by France, a couple of years old now I think, that we are almost certainly being visited, release of records by Brazil, etc., etc.
I think a major irrefutable event could be harmful, even though people will ALWAYS find a way to deny such a thing if the really want to. But, this gradual approach seems to be working, my own personal change in attitude about a year ago being an example.