My argument is that the system is good enough to get the kids to their biological upper bound. Otherwise, we would be able to increase their IQ further through

My argument is that the system is good enough to get the kids to their biological upper bound. Otherwise, we would be able to increase their IQ further through other means, but it seems we just can't. I don't think the school system is necessarily efficient at it, but kids do spend an insane amount of time in school. I imagine people would reach their athletic upper bound too if they spent 8 hours a day in the gym from the age of 5 to the age of 18.