I did not intend to turn this into a discussion on real art—there's certainly plenty of people who produce amazing work without training—but you're fooling yourself if you think art school has no value to artists. There is so much more to appreciate about what you already love if you know what to look for; there are so many ways to push yourself you might not consider without other experienced people.
"Artist" can be misleading when it is used as part of a job title—not all people with those titles do something that you, personally, might identify as art.
I've spent time in art school, both gallery-oriented programs and commercial programs. Neither was without value. But I strongly agree with the thesis of the original article that art school is not worth the immense debt you'll have to take on in today's America; I'm old enough that things like "grants" weren't impossible to get when my family was paying for college. And college hadn't gone through the huge inflation it has in recent decades.
"Artist" can be misleading when it is used as part of a job title—not all people with those titles do something that you, personally, might identify as art.