Raaarty
Problem with all your theories it relies on thousands if not millions of people keeping quiet and we know that would be impossible as so many would talk especially those in power to belittle their predecessors and political opponents. Too many nations are involved also and the Russians and the Americans were barely on talking terms for a lot of the time so the chances that they would suddenly agree to cover up something that would only benefit the Americans is very very doubtful.
Mate, how do you know that? from experience or what has been fed to us via the media. We need to think for ourselves not blindly accept and be led like cattle.
Consider this, even today more revelations are being revealed about WWII and deals done between countries even Germany and Allies, being Russia, US, & Britain for political gain.
Keeping your mouth shut, about say a moon landing hoax, benefits you, as you know it is impossible and you do not need to expend time, money, resources or peoples lives to duplicate or even better it. Think Sputnik and Russia and the so called satellite race. So it is in your interest to shut up about it.
And yes, as said in the fullness of time the cover up, because that's what a conspiracy is, will eventually come to light as the "guardians" die off and access is obtained to classified records/data.
But to say such cover ups cannot, did or will not happen is to deny the existing evidence. Even in your own Parliament. Weapons of mass destruction. Yes some are outlandish and can be easily dismissed others are far more plausible and bear further investigation. Don't forget the release of hacked security emails/information, by Snowden and others. Pie in the sky, no, shocking facts that make you think twice about what is happening.
You can continue to debate the subject for and against, but at the end of the day you need an open mind and I am not convinced that they are all 'theories'.