There was no way Neil could have really prepared for a manual landing in the low gravity of the moon. In fact when they tried to test it on Earth, it very nearly killed him
That seems like an incomplete summary of the story. You're neglecting to mention all the successful flights Armstrong had in the LLRV, not to mention the successful training he received on its successor, the LLTV.
I don't agree that it was "purely" Armstrong's intelligence and attitude that resulted in Apollo 11 success. He also received a great deal of relevant sophisticated training.
The Lunar Landing Research Vehicle was jokingly known as "the only thing more dangerous than landing on the moon". Three LLRV/LLTV craft were destroyed in crashes where the pilot ejected. Despite this, the LLRV was instrumental in making the lunar landings successful.
When future astronauts will train for the next lunar landing, it will surely be done in computer simulations. While it's obviously safer, the element of danger in the LLRV was probably quite character building. Armstrong had nerves of steel when he landed the Eagle in a field of house-sized boulders with just seconds of fuel remaining and alarms ringing in the cockpit.
That seems like an incomplete summary of the story. You're neglecting to mention all the successful flights Armstrong had in the LLRV, not to mention the successful training he received on its successor, the LLTV.
https://en.wikipedia.org/wiki/Lunar_Landing_Research_Vehicle
I don't agree that it was "purely" Armstrong's intelligence and attitude that resulted in Apollo 11 success. He also received a great deal of relevant sophisticated training.