The money is taken by middlemen. Spending lot on education is necessary if you want good results, but it's not enough if there is lot of corruption in the system.
We spend more on education that practically anyone else, and we spend more on it that we had in the past, with very little difference between now and then.
Some of the countries, like Japan, are close enough to racially homogenous that the results wouldn't be affected. For France or something it would be more interesting to see racial breakdowns, if the data existed. I don't think that means the comparison in the chart is arbitrary
That data does exist but is mysteriously excluded. Perhaps because it doesn't support the race bait? Moreover, contrary to the figure's claims, PISA does not exclude immigrants. It's just a hodgepodge of crappy statistics. Don't get fooled by anonymous Reddit posters.
The US has excellent post-secondary education. K-12 seems to be a mixed bag at best, especially in bang-for-the-buck terms.