There's a difference between a repairman and a teacher.
The repairman's techniques are immediately assessable. If you pick up your car and it doesn't work, his technique failed.
A teacher's results are not obvious until many years after the fact.
It is for this reason that when purchasing a car, we expect manufacturers to use engineering processes informed by scientific study that lead to longer-lasting cars. When mistakes in their quality are discovered, their cars develop particular reputations and sometimes have to be recalled.
Indeed, and that's why teachers are analogous to repairmen and the engineering equivalent is called a researcher in education science. The latter has nothing in common with teachers and effectively doesn't teach except sometimes at the college or university level. It's a bit rich to blame teachers when they're not actually empowered with the ability to redesign pedagogy principles. Additionally, everyone bitches about the lack of research, but I'd be very interested to know how many financially able families would keep their children in an experimental school ('cause you'd have to inform them). Interventional education research has a huge selection bias, and I'm speaking from personal experience.
All in all, the schooling system issues are analogous to those of the industry. How often do I read about devs complaining that management is stupid and academics are in ivory towers and know nothing of the front lines? Certainly, many teachers are quirky, but people dismissing them altogether live comfortably in their fantasy world.
There is a lot of education research done in both public and private schools. Everything from the school lunch programs to textbook paper has been invested, in practice itβs largely ignored because education is very highly politicized. Mandates for more testing are pushed by companies that administer standardized tests etc etc.
Something as simple as testing which Math textbook to use is never part of the process.
The repairman's techniques are immediately assessable. If you pick up your car and it doesn't work, his technique failed.
A teacher's results are not obvious until many years after the fact.
It is for this reason that when purchasing a car, we expect manufacturers to use engineering processes informed by scientific study that lead to longer-lasting cars. When mistakes in their quality are discovered, their cars develop particular reputations and sometimes have to be recalled.