> Then we should not depend on people making the right choice.
Broadly speaking, any system that depends on an unbroken chain of good people who do the right things out of the goodness of their hearts is bound to fail much sooner rather than later. So I agree.
The system should be designed so that people taking action out of their own interests nevertheless advances society as a whole. As Adam Smith put it: "It is not from the benevolence of the butcher, the brewer, or the baker, that we expect our dinner, but from their regard to their own interest." The system that was designed this way is capitalism, warts and all.
> One idea here is more progressive taxation.
I'm not sure how that conclusion follows from your premise. If you want to set up incentive structures such that people chasing their own interests also ends up being useful for society, then you want to make sure that people voluntarily pay money for goods and services that they value. The supplier of that value makes money, the consumer of that value is better off, and society as a whole is enriched as a result.
This also means that the state takes action to break trusts and monopolies, and (more difficultly) guards against regulatory capture, all of which end up making it so that people involuntarily pay for goods and services that they don't necessarily value. Rent-seeking behavior such as this is one of the highest economic ills.
"More progressive taxation" does many things, but it is also exceptionally good at enriching the politically well-connected, often in the form of rent-seeking behavior I described above. Look at world government spending as a fraction of GDP[0] as a good proxy for "more progressive taxation", and tell me between France (58.5%), the US (38.5%) and Singapore (15.4%), which you consider a well-run country where people do more useful things for society.
[0]: https://en.wikipedia.org/wiki/List_of_countries_by_governmen...