@Brieandcamembert
You have full control over what your child is taught abd so they potentially only learn what you know about. What you want them to and things from your perspective.
They don't get the same social opportunities.
They don't learn how to be with people they haven't chosen to be with & to do things thet don't want to do.
They have less time away from parents to learn from other people
They are likely to be accommodated far more at home than school so resilience is lower
It's a very insular way of life that means you are exposed to far fewer variables.
With the exception of the first point, the rest of them are not the negative points you think they are. In fact, they are the absolute reasons that my DC thrives at home and was nearly broken by school.
Your first point however; my DC learns differently, they have a better general knowledge than I do, they don't need GCSE level maths and they have taught themselves more than I ever could. She is 14 now though and learning in a way and to a level that suits her needs and abilities.