What? Education needs to scale because everybody needs education. Highly personalized education requires decreasing the number of students assigned to each teacher, which in turn would require a huge increase in education spending (and also short-medium term labor shortages in the field). Rich people who spend $100k/year on their children's education are doing the best they can for their children, but unfortunately it is not even nearly feasible for everyone to be educated that way.

Also, it's about cost effectiveness, not just cost. The more parts of education that are scaled, the more money can be spent on other programs that can enrich kids' lives, which we currently don't have the money for in some cases (e.g. music programs, special ed, special programs for the gifted, actual educational research).