To be more specific:
Obviously the plot is about discussing Peter Pan in relation to Transhumanism, very much paralleling to that issue I mentioned before of infantilism being intrinsically connected to those who reject the material for the immaterial seeking the true mind.
In Alien Earth, the mind transplant->ascension to transhuman is only possible for children because their minds are not yet molded by the material.
But this whole view is misguided, seeking god through trans-childism is not the way.