Benefits of learning online yourself is that you're self motivated and you get access to the best resources (better than the teacher you are forced to listen to)
But what is the teacher teaching from? Generally they are working off seminal and highly-regarded texts that the autodidact set would tell you to read anyway.
I will grant you that the current form of the education system, especially in light of how easy it is to engage with the primary resources nowadays, is massively inefficient and needs an overhaul to provide more individualized learning. Something like Alpha School is promising in this regard. But don't throw the baby out with the bathwater. Even if a kid today learns entirely "on their own" with an AI teacher...neither them nor the AI accumulated that knowledge, and we still need that infrastructure of people contributing to advancing and refining the shared knowledge base.
I will grant you that the current form of the education system, especially in light of how easy it is to engage with the primary resources nowadays, is massively inefficient and needs an overhaul to provide more individualized learning. Something like Alpha School is promising in this regard. But don't throw the baby out with the bathwater. Even if a kid today learns entirely "on their own" with an AI teacher...neither them nor the AI accumulated that knowledge, and we still need that infrastructure of people contributing to advancing and refining the shared knowledge base.