Big deal if a few studies find super teachers make a big difference. Maybe the studies are rigged. Maybe the effects are not long lasting. A few thousand super teachers exist while thousands of times that many students exist.
Sure, we could practice eugenics, including cloning the super teachers, but the current establishments are fanatically opposed to eugenics--and are getting more dysgenic every day.
Today's students are too low IQ, ethnoracially diverse, and enveloped in cultures of hostility.
And much of the hostility comes from the fact that the curriculum, beyond basic reading and math, is filled with garbage that has no practical or ethical value, not to mention the cultural Marxism. I once knew a high school auto mechanics teacher. He found multitudes of decent jobs for his medium IQ students. He was a job creator. So what happened? The school district decided to replace the auto mechanics classes with vague, vapid technology classes--the sort of classes where you make worthless objects out of Popsicle sticks--on the unsupported opinion that doing so makes students more creative, confident, and well-rounded.