I hear the frustration, and I identify with it. I'm glad you have solved the problem for your daughter. In spite of the Slate article, I don't think you are evil for sending your child to private school. If I had no options for a good public school, I'd probably look at alternatives too.
The problem though isn't completely personal. It's social, which I think was the essence behind the provocative title of the article. It's a social problem because not all of our children have parents like you or me who are willing to look for those alternatives.
It's in our social interest to educate as large a swath of the population as possible. As tragic as it is to say, the vast majority of parents aren't interested in finding the solution. They often send talented boys and girls to school after telling them that school is a waste of time, or more often never mentioning school.
Public school is vitally important because those kids deserve a chance too, and right now, I'll admit, we aren't giving them the best education we can offer. I can tell you that the teachers and administrators are, for the most part, going into work every day wondering how we can make school more meaningful for our students. We lose sleep over the disinterested students, specifically the talented ones. We try to make it interesting and engaging, but we are blowing against a very strong cultural wind that does not originate in the school. It is the collective force of an indulging society. That's the fight we need to fight. That's the change we need to see.
While I realize you are frustrated and have found a great alternative for your child, public school is still an important issue, and I'm saddened to see your energy sidelined because you found a solution for your child. There are other kids out there without parents as caring as you seem to be.