without meaning to offend any teacher reading this, I think you are vastly over-stating the skill of purely conveying knowledge + skills.
I say this as someone who taught previously, and now works in higher education, in education research.
The greatest difficulties and skills of primary and secondary school teaching are actually nothing to do with the basic transfer of knowledge and skills from teacher to student.
They are to do with making sure that transfer happens within such a difficult setting. 20-35 children, behavioral issues, schedules, ever growing administrative work, curriculum that can shift with the political wind, poor school management etc. etc.
That is the genius and skill of most teachers, being able to maintain the transfer of skills and knowledge, in an environment where everything is making it very hard.
Take that same teacher and give them 1 child in a nice home, and tell them to teach them the years worth of content.. and they will be done in a few months. It is that much more easier and efficient, dealing with a single child at home, than a class in a school.
So in short, home schooling parents (the good ones) don't need to be anywhere near as skilled or trained as teachers, because in general their role takes the most natural part of the job of teaching, and avoids almost all of the hardest parts.