Going back to the OP, I really firmly believe that moral compass is learned at home, and if you have experience of both sectors you will know that there are "amoral" people in both sectors - that's just life. Money or class is not a guarantee of superior or inferior morality.
That doesn't mean there are not problems in both sectors. Smaller, less successful independent schools are struggling for pupils. State schools are struggling with cuts, a growing population and lack of new schools and resources. There is also an ethos problem in state schools, and in my opinion is due to the fact that the direction isn't one that is serving the general public, but more government targets.
This is indeed a political issue, but not one that is being addressed. The current department of Education seems to be going in the opposite direction - e.g. less funding and more targets. Everyone is under pressure and some of the more popular independent schools are thriving because of it. My eldest daughter is at one of those and there has been a huge surge in demand - and that's nowhere near London.
I think that says something about how unhappy many parents feel with the situation and do not have the power to change things as politicians are not listening to what parents want and need for their children.