As always, Dr. Williams is right on target describing both the problem and the solution in his concluding paragraph.
I taught remedial mathematics at the college level. At most only a few real adults were able to master the dumbed down material, and they were there just to review math before reentering college. All but maybe one or two students under age 26 were failing the course, many for the second and third time.
He is exactly correct in saying that students that cannot pass entrance exams should not be allowed to enter college. They should go back to high school to make up their deficiencies. We might even get better high schools that way.