This will just be grade 13 and 14. Endless childhood.
What we should be doing instead is reducing the number of years of public education to 8 or 10 grades at the most (with the same educational attainment expected now in 12 grades).
It already is - a neighbor teaches at a local juco and said so many of the kids can’t pass an entrance exam so they offer remedial reading comp/writing/algebra classes - so these kids are paying college rates to learn what they should have learned in high school for free.