He is not the oldest or wisest man on the planet. He is an imposter.
Odd that we refer to hanging the meat as "aging" and yet no one has mentioned what part the 'age' of the animal plays.
It is more important to get the animal dressed and cleaned and COOLED as soon as possible. Once that is done then decide about hanging it.
I've processed deer within a day or two of killing when it is a young animal, and I've also hung Moose and elk for up to 3 weeks when they were old animals. Reliable temperature is very important as well.
I find it hard to believe that a moose that is field dressed is frozen solid the next day. It may have some freezing on the outside few inches, but it takes a long time for the core temp on a hind to cool.
I have gone on extended trips where a couple deer were killed in the first few days. It was warm so we skinned them and covered in cheesecloth. We normally leave the hide on to keep the meat clean but because of the heat we skinned.
Over the next few weeks the temp dropped and by the time we got home and started the processing, a couple deer had been hanging for 3 weeks+
They had lost a lot of weight due to moisture loss. There also was a dark 'skin' on them. The skin helped keep the flies off, but it is trimmed off because of esthetics.
The deer was very tender and tasty, the down side was the shrinkage.