You're assuming kids have the extra time for that. Homeschooling also is much more time efficient. There's a lot of time eliminated even you're not trying to get a whole classroom on the same page (literally and figuratively), and leaves more time for play, extra curriculars or special interests and positive socialization, things that existed more prominently in education when there were smaller class sizes. You can also cater more to where the kid is at in a subject, moving faster in subjects they excel at and slower in subjects they struggle with, as well as accommodate any learning disabilities or idiosyncrasies as well as age specific level of brain development (huge differences in comprehension levels with just a six month age difference in certain subjects. It's also what the ultra rich and children celebrities effectively do, purchasing a bespoke individualized education plan just in a class of 4-5 in private school.

I always laugh at the people insist it's best to let their kids be guinea pigs while public school systems which aren't even utilized but it's most vocal advocates for their own children are on a multi decade track of "figuring it out".