The picture I have of the US education system is that there are a large number of smart, dedicated, people spending a lot of money trying get the best outcomes they can with the students they have to work with. This is all irreconcilable with the claims the OP makes.

Not so irreconcilable, if you don't suppose that "a lot" means "most."

The current average likelihood of a high school freshman in America making it to graduation is about 78%, and that's the best it's been in quite a while.

At the public high school I went to, it was a pretty big deal if a year passed where someone failed to graduate, and students would ask each other, not if they were planning to go to college, but what college they planned to go to. The only student I ever asked or heard asked that question who said they weren't planning to go to college, went to college. And not a two-year or community college, but a pretty decent state college.

That was a good high school, but it wasn't by any means renowned. With schools like that bringing up the national average, consider the state of the schools dragging down the national average.