This is probably bound to catch on fast in the us where teachers and their unions are thought (by an unnerving possible majority) to be one of the primary factors in our ongoing economic problems.
a program that only admits 18-30 year olds will replace education of minors in the US?
This article had a catchy headline, but what is described is not much different from how most of my classes were in college. They've just removed the couple hours of lecture and instead just give out the problem sets. There is no democracy in choosing the problems you are solving, or any encouragement to explore things that interest you.
Alternative education programs like this don't have to be capable of replacing traditional education to be a success.