After thousands and thousands of years of human existence, there are plenty of people who won't be remembered for some grand historical event or infamous wrongdoing.
900,000 years ago there was what evolutionists call a bottlenecking of the Homo heidelbergensis line of human evolution. It is estimated that only a little over 1000 survived and grew very slowly over the next 150,000 years.
It was touch and go, however it did magnify the one source idea that you allude to; although in a less philosophical way. Each one of them and every ancestor which followed played a huge part in us having this discussion today. It is only through labelling and value judging their existence that makes some individual shine more than others in our mind's eye.
I believe we return to oneness —
One must wonder if we ever left it. Perhaps it is simply obscured by the ego's busy mind which tends to focus on the "me". It seems that putting someone or something before oneself is a good means of breaking that process of Thought.
Steven Levine has the great allegory that thoughts are like clouds drifting across the sky of our vast and open mind.
The thought (some may say the ego) has a means of capturing us in those clouds of thought, be they dark or fluffy white.
After enough cushion time one will begin to likely see how thoughts are connected. By thinking about a person or thing one can quickly travel along that train of thought. One will see over time that these are often not random and by thinking the thought again our mind will summon the same series of thoughts to arrive at the same landing. If that landing is a place of anger than emotions take over to separate us further from the One. Pleasure might do the same by thinking of an attractive person one might end up consumed by sexual fantasies when having a thought of that person. There need be no value judgements for the thoughts as traditional religions tend to teach. To them some thoughts are sinful while others are not. My feeling is that there is only the potential of being mentally removed from the One regardless of its good or bad label.
If the same mutated DNA marker can be found in me and my 900,000 year old ancestor one has to question the concept of leaving and rejoining the One.
For me there are those moments of joy when feeling (as opposed to remembering) my connection to the One; as fleeting as they tend to be.
Without turning this comment into a post it is beginning to be allow me to let Erich Fromm explain life's hack to bring us to the realization of the One in his concise overview in The Art of Loving.
✌️ 💛