Nicely argued and supported. You should consider turning this response into its own article.

I think, though, that you are marrying effect with intent and reaching an unsettling, but also implausible, conclusion.

Yes, our school structure most certainly does effectively function best when students are compliant and homogenous. As a result, it very much ignores, even discourage, individuality, difference, etc.

But there are two hard truths here. The first is that in a large, complex society, most individuals - statistically speaking - will most likely find some measure of stability meeting needs by being compliant and suppressing their individuality to meet the demands of whatever institution they find themselves. That is, being homogenous to their workplace.

The second is that cheap, mass education is most effectively achieved through the current school structure, regardless of all the other deleterious, even counter-productive effects.

Thus, there's no need to imagine some form of massive nefarious plot by secretive oligarchs to create a mass of compliant workers. The rich and powerful simply benefit from the system, for a host of reasons, compulsory education systems being merely one of them. It's a bit outlandish to claim they've created a system that benefits them so much when one hardly needs a conspiracy for it to exist in the first place.

The myth of the factory education is that it's specifically designed to create factory workers and conditions. Those who actually design and implement curriculum, content, and pedagogy are academic university professors, not businessmen, not even politicians mostly, and certainly not the oligarchs.

The most compelling evidence for this, beyond the fact that everyone involved in teaching in a school actually is an academic in one form or another, is that all the courses and content and pedagogy completely align with the concerns, skills, and content of academia and little else.