If you understand that, then you understand that homeschooling is a reasonable option if you want to ensure your child has a proper education. It would become your responsibility instead of offloading it.
Being a doctor does not ensure that they will always diagnose your symptoms correctly. Therefore, using your logic, we should all just self diagnose and not use doctors at all.
We can be reasonably confident that we can teach a simple curriculum at home, and know there will be no disruptions or bad compromises. These are not complicated, they're comprised of things every adult ought to know. By contrast, we cannot be reasonably confident that we make medical diagnoses without training.