We could also have trusted that the then USSR and China and other nation would have tattled if we had not gone to the moon.
Imagine if Putin wanted to rattle Americans’ cages by saying that the USSR knew Americans didn’t go to the moon and played along in order to get certain “concessions” from America!
This topic (Russian reaction) is covered in depth in this book:
https://www.amazon.com/One-Small-Step-Great-Dominate-ebook/dp/B07NB2QL13
We are talking quid pro quo from Nixon/Kissinger here.
Also, it seems to me that the effort to ‘fake it’ and keep that secret would be incredibly difficult. It’s much easier to believe what seems to all logic to be the case: we went to the Moon.
There is a deep state for each nation.
We can have no clear idea what the USSR or the CCP would have done.
What we can know for certain is the answer to the question of trust in government and its media.