I see the logic of that argument. By the time he's 18 DS will have no real assets of his own.
There are extremely few rich 18yos.
He will however have had the benefit of two graduate parents (and a graduate nanny), a quiet warm bedroom with desk, a house with more than 2500 books in it, a private education at a school that has one of the top Oxbridge entrance ratios in the country. He will be taught maths by a maths graduate who I've met and is good, a French teacher who is French, and soccer by someone who used to play professionally for West Ham in the premier league. His school does not do the fake arty "science" combined GCSE, and at the age of 5 he's being taught computers by someone who charges banks more per day for consultancy than the average IT teacher earns in two weeks.
We are spending good money and time giving our DSs an unfair advantage.
It is far easier to look at attainment than ability, so that's what most universties and employers do.
I see both sides of that. I recall a conversation with my dad where coming back from the pub he asked "mike's boy is doing O levels, are you going to do some ?" to which the response was "no, in a few weeks I'm off to university to read maths and computing".
We only had a computer at my school because we had stolen it In my year we had the same number of kids die before leaving school than go to university (bikes and motorbikes mostly), and the maths teacher had no degree in anything, much less maths. A level biology wasn't offered at all, and because we were deemed working class kids had no chemistry teacher for most of the O level.
I would have welcomed a few free UCCA points to compensate for this. However as someone who has first hand experience of how the system works from below I don't expect it to work well. It will be manipulated big time, and not for the benefit of kids who need it.