Most people don't think that there is evidence because they haven't look for it. There's such a little green men mindset in this culture. It's hard to work your way through that.
Getting someone from the government to talk is almost impossible.
We can't come up with a reason why this information is being withheld. The government won't even acknowledge that the incident took place but we know that it did.
There's definitely evidence of strange phenomenon in the world. These are well documented,