The author criticizes the way we teach languages in schools but I’m not sure you can do much better when most of the class is only there because they have to be there. Frankly, I think it’s remarkable how well schools do.
I think much of the value, though, is in the opportunity it affords people who find a passion in it. I really loved French in high school, and the combination of the support/resources it offered (a book, a teacher) and the regimen (I think French was either 3 or 5 times per week? I can't recall) was just right to let me learn as much as I wanted to, and also enough regimen to keep me coming back to it even if I wouldn't have otherwise necessarily felt like it if left to my own devices.