Through most of human history through most of the world; most people dies in the womb or during infancy - plus significant numbers died throughout childhood and adolescence. Only a small proportion reached mature adulthood.
This seems a neglected fact in theology - which generally assumes that Men live a full lifespan.
So - the usual, typical, statistically-normal human condition is to be incarnated (ie. to have a physical body); and then to die either almost immediately (miscarriage); during fetal life (spontaneous abortion); just-before, during or just-after birth (neonatal death), or death in infancy (first year of life - generally before the dawn of consciousness).
This is the human condition. This is the Life that Christian doctrine needs to explain. This is what religious metaphysics or theology primarily ought to make-sense-of...
On the whole; I would say that most versions of Christians do a poor job of it! Mormonism, on the other hand, explains that our pre-mortal spirit selves need to be incarnated, to receive a body - in order to progress to god-hood. (That is small 'g' god-hood.)
Thus, incarnation is vital in and of itself, and regardless of how long someone lives, or how much experience they have in Life. SImply to be incarnated as a embryo and then to die is sufficient for this purpose - after this, the person may be resurrected to eternal life, and it becomes possible that they can (if they choose) progress to full godhood; but without incarnation this is not possible.
For Mormonism, incarnation is superior to spiritual life in that sense of enabling full progression; because incarnation is linked to free agency, to divine personhood.
But the superiority of an incarnate is Not in the sense that incarnated persons are superior in virtue to pre-incarnate spirits - that is Not true.
A pre-mortal spirit may be, probably usually is, far more-Good than an incarnate human - but for a spirit theosis is limited, whereas the mortal incarnate has taken the next step.
For Mormonism, to have received a body is therefore Good from the perspective of enabling further progression towards divinisation, in and of itself; no matter what happens next. And the mass-majority of humans who died in the womb or as children have thereby attained something of crucial value.
The experiences of a long-life offer further opportunities and choices and possibilities - for good and for ill; but in the divine plan and scheme of creation as modified for each of God's billions of children, adult maturity and a full lifespan is Not necessary for most individuals.
People such as you and I are therefore an exceptional case...