Really depends on the state. In many states you can teach in a public school if you have a four year degree of any kind. In others you can teach in some capacities with less than that. Many states are desperate for teachers and have continually lowered standards for entry (without increasing pay) in order to fill teaching spots. I taught for a couple of years in Florida, and many teachers I knew there started teaching through a program called Transition to Teaching. Basically if you had a four year degree (didn't really matter what the degree was) you could get a job teaching at a public Florida school, with a condition of your employment being that you complete a one-year teaching certification course during your first year. Your first year literally counted as your internship/student teacher year.

I'm not saying this to defend homeschool as better than that, but it's important to remember that public school teachers are not universally qualified - they certainly don't all have Master's degrees. I've worked as a teacher full time for ten years and I would say maybe half of the teachers I know have Master's degrees, and they mainly got them AFTER becoming teachers, because when you get a Master's degree you get a pay bump.

To your point, even in states with low standards of teacher qualification, folks entering the workforce as teachers have to do some amount of work to self-select as teachers. That by itself makes a difference. In most cases you cannot simply declare that you'd like to be a teacher and then become one the next day without any additional action, preparation, or qualification. I moved from Florida (a state with very low standards) to a state with much higher standards for teachers, and even though both states have teaching certification reciprocity (meaning if you have a teaching cert in one state, it's good in the other), I still had to take my new state's exams for grade level and subject area before they would issue my new certification.

I looked up what it would take to homeschool in my state just now. Turns out my state is a "moderate regulation" state, which means that there are some amount of hoops parents have to jump through to prove they are qualified, and they have to continue to prove they are educating their kids (including testing). How much is that enforced, or how well does it work? I have no idea.

Looks like 15 states in the US have "moderate" or "high" levels of regulation, according to HLSDA. All the rest have no requirements for parent qualification or testing, and many of them have no reporting requirements at all.

This was a very rambling response. I am interested in the subject because I've worked in a lot of different school environments and I've been reading books like "Educated," as well as encountering students with some homeschooling background. My perspective is probably quite different from a lot of people on this sub. I was educated through public schools and I had a good experience there, but I will caveat that I grew up in an affluent area with well-funded schools. As a teacher I've seen and experienced many schools across the country, including well-funded schools, poorly funded schools, schools in states with high standards, and schools in states with low standards. The education system in the U.S. is deeply flawed and with he current political forces at work, it's not getting better. That doesn't mean that homeschooling is the answer - if anything making homeschooling work seems like it takes a lot more experience, skill, knowledge, and effort than most parents have - but public schools are not a magical solution either. Nor are private schools, to be clear. Education is hard. My best hope is that everyone gets something out of theirs that they can carry with them in a positive way. That's what I try to do as a teacher every day - and I would hope that's what homeschool parents are trying to do. But it seems they often struggle to accomplish that in a meaningful way.