The Long Walk is analogous to a sperms journey to the egg
Okay so I just watched this stoned, and then came to a realization at the time the one who wanted to write a POV book about the long walk that they are sperm.
Think about it, the goal is to be last one in an endless journey. They each all formed bonds where they most likely won't find one another in each company, hence they're sperm since the sperm contains a man's trait (which is why no boy is similar to one another).
Each boy (or sperm) that dies is a trait and personality that won't transfer over to form the baby.
The major is the father (literally), especially when Stebbins said that he had bastards all over the place.
Garraty is a trait that is a recessive that a father wouldn't want to be passed on, which explains his backstory.
Baker is a trait that's god fearing.
Holson is a trait that's cheerful.
Baskowitch is the asshole trait.
The Indian is also a recessive trait, maybe because of lineage.
McRievs is the trait of having a positive outlook despite of burdens.
So yeah, Long Walk is a sperm's journey to the egg.