I concur.. Could a human life's express purpose is to prove "to US" what we are made of.. meaning what we are capable of, or not.. Testing our qualia, hopes, and dreams.. or lack of them.. for our own information and judgment... Not to prove anything to God..
And that "the TEST" is not a fleshly test but a spiritual one.. A spiritual test of spirits.. inverted into the flesh for a time of testing.. Pure genius this test.. Humans self-sorting themselves into sheep pens of every kind and shape.. (John ch 10).. Or even into goat or pig pens.. And the prodigal son story(metaphor) carries more impact than we can know.. with only implied other options than those stated.. The prodigal son had many other possible options than the one taken.. Lived out daily by many I've known and been acquainted with.. sometimes with trajic results..
From Genesis to Revelation, Alpha and Omega - "all that there is" unfolds to that final cause.
And he is the head of the body, the church: who is the beginning, the firstborn from the dead; that in all [things] he might have the preeminence. For it pleased [the Father] that in him should all fulness dwell; And, having made peace through the blood of his cross, by him to reconcile all things unto himself; by him, [I say], whether [they be] things in earth, or things in heaven. Colossians 1:15-20
To God be the glory!