You are dealing in how things have been, not how they could be. Some private education has been as you say - but in the context of the current educational environment. Also, some private education has been quite effective.

Most public education I would say is thinly disguised loot and pillage as well. It sometimes, happens to provide some level of education. But that people like yourself come to an assumption that there is nothing for the "bottom 75%" to do, as opposed to "we have not figured out what bottom 75% will be doing, yet. But they will figure out something or be able to acquire the skills to provide value in return for value" is in fact something I attribute directly to extremely poor public eduction.

Many people have a difficult time being agile in the employment marketplace because our crappy education does not prepare them to be agile, and finding time/finance to be agile as adults is still something our society struggles with. Also as an aside, private education night classes/CEC/Massive Online Edu/etc have been probably more effective than anything else in helping alleviate the problem.

There will always be things to do, and ways to provide value as long as people are able to adapt to what the greater market needs. Education is a catalyst for that type of adaptation. If we expect people to adapt to changing market environment, we do need to make sure the tools by which people are able to do so are made available.

I for one do not buy into the "there will be nothing to do" line of thinking. When I hear that, I interpret it as the speaker saying "I do not know what the employment scenery will be like, I just know it will be different and since jobs that exist today will not exist tomorrow therefore that means there will be no/fewer jobs". Which I view as needlessly pessimistic and quite short sighted. 75% permanent unemployment will only occur if public forces contrive to stifle market dynamics.

For who could be free when every other man's humour might domineer over him? - John Locke (2nd Treatise, sect 57)