Sex abuse scandals often thrive thanks to blackmail. This only really works if a fair number of those involved are powerful, both because they can blackmail other people and because they have a lot to lose. Your average backstreet sleazebag gets outed faster - the Rotherham and Rochdale traffickers weren't protected as such, their victims were disbelieved due to prejudice.
With Epstein and Savile, ordinary people did know and blew their whistles. They were similarly disbelieved, partly through prejudice and partly due to silencing by powerful people with skin in the game. Same again for many other sex abuse rings. Savile was so confident in his power, he wrote about his abuse of young girls in his autobiography: no cover-up there.
Liverpool did not shut up!
There simply isn't the same motivation for a deceit like the Apollo landing(s) being faked. Apart from the logistics, with hundreds of thousands of people having to lie and nobody saying anything, there's the obvious fact that Russia would've been on it straight away. I imagine they did try to show it was all pretend, but failed.
If there had been huge financial gains in it for a particular group of powerful individuals, and their motivations were so strongly personal that they'd kill or otherwise destroy anyone who tried to expose them, there might be a shred of truth in it. In reality, the scams and scandals associated with early space exploration were on the level of suppliers charging $3,000 per coffee machine and materials developers lying about their products' capabilities (they were all caught out eventually).
By saying it's all fake, you're really insulting people like Buzz Aldrin, Neil Armstrong, the many dedicated engineers and the famous 'Hidden Figures' mathematicians Katherine Johnson, Dorothy Vaughan and Mary Jackson.