Education is part of it. But a lot of the social capital which makes societies prosperous is separate from what we usually consider to be education. On an individual behavior level that includes things like knowing how to show up for work on time, sober, and properly dressed, and follow management instructions without arguing or taking things personally. These are skills that people in the middle and upper classes take for granted but they forget that there are a large number of fellow citizens in the economically disconnected underclass who never had a good opportunity to learn those basics. As a society we've never done a good job of lifting those people up.

> On an individual behavior level that includes things like knowing how to show up for work on time, sober, and properly dressed, and follow management instructions without arguing or taking things personally. These are skills that people in the middle and upper classes take for granted

I don't see your point.

Those rules does not apply to the upper class and middle class workers have way more leeway regarding that than the lower class.

The existence of an upper class necessitates the existence of a lower class. You can't just pull everyone up to be above average.