If you are world-class talent (someone who gets to Oxford), you should be capable of similar results as kids from independent schools. Like Joe Seddon did (https://en.wikipedia.org/wiki/Joe_Seddon - growing up with a single parent mom, working as a therapist in NHS).
It isn't fair to ask ones to have 4A* and others to have just 3As.
Only 1 in 2600 gets 4 A.
And 1 in 83 gets 3 As.
Making it 31 easier for people from state school is discrimination so bad, it should be illegal.