The important thing here is that wealth is not making a difference to this, it is just a by product.
Re-read two of my earliest statements in this discussion:
I imagine the key differentiator is the quality of primary and secondary education.
I actually said the key difference is the quality of primary and secondary education, and within that I included basic values and work ethics as they are learned behaviours, not money. Money is just a facilitator.
You've then gone on to say:
A rough summary is basically a child's intelligence is roughly 50% hereditary and 50% environmental, with the environment mostly being related to the child's family environment.
I agree, and I think the above shows we agree. However, I disagree with:
The important thing here is that wealth is not making a difference to this, it is just a by product.
Money is not simply a by-product, it is a facilitator and does make a difference. Poverty impedes education and intellectual growth, and wealth helps exploit what natural and learned advantages a child has. Your original statement that I took issue with was:
This is just nonsense. In the UK anyone can go to university if they have the ability
My comment was that any implication that the UK is a utopia of equal opportunity and meritocracy is a sretch of the imagination. We have good systems in place to try to afford people every opportunity, but they are not universal and bad environments (i.e. lack of good learned behaviours i.e. work ethic, and lack of good primary and secondary education) significantly impede people's chances.
If you are born in to a disadvantaged family without good intellectual genetics, you are pretty much a lost cause; without any particular natural ability, and without a good environment and education to foster what you do have, the chances of you becoming a success are slim. Conversely, if you have those same genetics and are born in to an advantaged family, you will be afforded significantly more opportunities. Completely take attitude or work ethic out of the equation, and the simple fact that your parents have money means that they can provide some aspects of a better environment. If they were to ship you off to Eton at a young age I'd think you'd fare better than at your local comp.
All the pieces that are involved are complimentary, and if you a particularly defecient in either genetics, environment or afforded opportunities you are going to very much struggle. I do not believe that the afforded opportunities that wealth can provide are unimportant.