It’s a tough one. On the one hand, parents should be free to raise their children how they see fit. On the other hand, uneducated idiots tend to raise their children to also be uneducated idiots. For a stark example of this, in my area NextDoor is full of parents writing long posts about how horrible our education system is for forcing their children to wear a mask or get vaccinated, so they are pulling their kids out of the education system to homeschool them personally. Invariably these posts are full of spelling and grammar mistakes. So, great - you lack even a basic grasp of science and math (or you wouldn’t be so against the COVID response), you can’t spell or write for shit - and now you are going to be the only source of education for your kid? Yeah, that kid is fucked.
I don’t know that there IS a solution to this issue that doesn’t get into some weird and morally dubious social engineering. The only thing I keep coming back to is, it is a problem that our society values things like wealth, physical appearance, wealth, athletic ability, and wealth so much more than intelligence or education.
But that just gets us right back to where we started. Parents who lack education are less likely to value it highly, and why would they WANT to instill an appreciation for education when they themselves don’t value it? And as you point out, it’s not like they don’t value education because they’re horrible people who have personally failed; for the most part, people who don’t value education weren’t raised to value education, and now we’re having the same exact discussion one generation removed.
People don’t make choices in a vacuum. The choice to raise your kid to have the sorts of values that would be beneficial to our modern world requires that you value those things first; otherwise, why would you care?