What if I told you that you that I had a reform proposal that would give us nearly all of the same benefits we gain from spending on Medicine and Education in First World Nations but for half of the cost? While this is a radical and bold course of action that would require substantial political capital to acheive, I'm not as madly optimistic as to expect the funding freed up to be spend on Efficient Charity or Existential Risk Mitigation (that is what Altruistic Piracy is for). Even slightly lower taxes resulting in higher economic growth lifting more people out of misery is not the expected result. I do expect it to be spent on things with some sorts of returns and that this is on net very good. I should remind you that even for the most inane use with some positive value you can expect pretty drastic net effects, these are not small numbers after all, developed countries usually spend more than 10% of their GDP on Healthcare and over 5% on Education. How many trillions is that for the entire Western world?
Certainly enough to buy mountains of non dead Third World babies if that's your thing. So are you ready to hear my reform proposal?
Cut societal spending on Medicine and Education by half.
One reason that people believe Hanson's claim that half of US money spent on medicine is wasted is that other First World Nations spend half as much per person. You seem to imply that Hanson claims that France wastes half of its spending and the US 3/4. He certainly does not do that explicitly.
The link "Gregory Cochran on Education" is actually by Henry Harpending (the other really is Cochran). As Harpending concedes in the comments, he really is missing something and this is not at all evidence of waste.
If it's worth saying, but not worth its own post, even in Discussion, it goes here.