I think a more honest analysis would not only look at other educational systems in other countries but use a unified metric, say, euclidean geometry or algebra

I think a more honest analysis would not only look at other educational systems in other countries but use a unified metric, say, euclidean geometry or algebra comprehension, something that you can roll back the clock 60 years on and still get comparable data. There's a multi armed bandit problem here of course but the law of large numbers should allow you to isolate what effect marketization has. I'd be shocked if it was positive. Human motivation is sullied and distracted by profit so the actual goals become incidental. If the alignment is close, like in commodities, it's all good. If it's poorly related, such as in education, it seems to be a problem. Privatization works poorly as a blunt magical instrument wielded on all problems