I think it's bringing up a couple of good points actually, that are worth considering when crafting public policy, and observing where our current society is heading.

1. Treating and thinking of our current public education system as "the great equaliser", such that children coming out of it operate at a roughly similar level once they leave, isn't actually a reality.

2. The outcomes of children, despite going through this "great equaliser" system, is actually still significantly affected by parents, meaning parents, and the way they interact with their children, still have a massive role in children's outcomes.

I think a lot of people, and teachers, have observed that parents appear to be increasingly farming out non-academic responsibilities onto the school system and teachers (e.g. discipline, life lessons, social expectations), let alone give time to help their child academically.

And I imagine a lot of this is due to themselves being overwhelmed, under financial stress, or simply having to work more hours less securely to cover rapidly rising living expenses.

All of this adds up to a picture that creating the conditions in our society where parents are under less pressure financially and mentally (presumably similar to conditions experienced by university educated and CEO parents) is likely to improve children's educational outcomes, and their future outlook and experience in life.

TLDR; it suggests easing life conditions for low socio-economic parents, such that it enables them to spend more time with their kids, would have more of an impact in improving their children's life outcomes, rather than focusing money and resources entirely on the education system to do the same. Admittedly some assumptions in there. But worth investigating.

And another reading could be that putting resources into making university more universally accessible, and something that is encouraged to be taken even by those pursuing careers not requiring university, and structured in a way to more easily and unobtrusively allow that, so that more parents had university experience, could be a better way of improving children's educational outcomes than putting the same resources purely into public schooling and children.