The problem starts with children not learning "enough." The first question is, "Why?"
Fortunately, Smart people have studied these issues and found that the usual culprits are poverty, homelessness, food insecurity, and family stress (divorce, parents unhappy, etc.). Kids do better when they get breakfast, lunch, and an afternoon snack/meal in school and have a safe place after school for studying and socializing. Teachers do better with enough money to eliminate their financial stresses and total funding for classroom basics such as properly maintained buildings, heating and cooling, and classroom supplies.
But instead of addressing these issues, some people shake their fingers at the teachers, proclaiming the teachers union is the problem.
Besides, you are simply attempting to change the subject. The OP was (allegedly) concerned that home-schooled children wouldn't be "reading at grade level". In many areas, public school children aren't "reading at grade level" either.
If "reading at grade level" is the metric, then why would public school be preferred over the home school? No one has cited any evidence to the effect that 66% of home-schooled children fail to learn how to read.
Why they're not "reading at grade level" is irrelevant. Whether it's because of the reasons you claim, or other reasons, it is clear that the public schools a) cost billions of dollars and b) are ineffective at fixing the problem.
I googled homeschooling and reading level; I found no discussion or documentation of the reading capabilities of homeschooled children. I don't believe it's possible to get an accurate indication of the reading level of homeschoolers. The dominant thought seems to be that "grade level doesn't matter" and that parents refuse to evaluate their children using the same tests as public and private school children. This refusal to participate in society and work by the same rules is part of why I think homeschooling is a considerable disadvantage for most kids.
If a process or organization is ineffective at solving a problem, it's usually because it solves the wrong problem. Understanding why the problem occurs is part of finding the right solution.
> I googled homeschooling and reading level; I found no discussion or documentation of the reading capabilities of homeschooled children.
Some research done in Australia found that homeschooled children performed above-average on standardised tests, including reading: https://www.smh.com.au/national/nsw/homeschooled-kids-perfor... ("NAPLAN" is Australia's nationwide standardised testing program for years 3 and 5; the "HSC" is the state of New South Wales' statewide year 12 exams, used for university entry)
Look: if you took your car to a mechanic, and the mechanic's only response, ever, was "It's not my fault. I can't fix it. Oh, by the way, here's a gigantic bill."
You'd soon stop taking your car to that mechanic.
Blaming societal problems for failing to teach children to read is exactly analogous to the mechanic above.
Even if true, that just means they're taking money under false pretenses. Taking money from people when you know you won't/can't provide the services you are offering is generally known as "fraud".
Fortunately, Smart people have studied these issues and found that the usual culprits are poverty, homelessness, food insecurity, and family stress (divorce, parents unhappy, etc.). Kids do better when they get breakfast, lunch, and an afternoon snack/meal in school and have a safe place after school for studying and socializing. Teachers do better with enough money to eliminate their financial stresses and total funding for classroom basics such as properly maintained buildings, heating and cooling, and classroom supplies.
But instead of addressing these issues, some people shake their fingers at the teachers, proclaiming the teachers union is the problem.