We need smart people in society so that we can advance. They are the leaders that will help move the needle. If we burden our best and brightest young people with "educating" their peers then we as a society lose out. The gifted children should be free to learn at their own pace so that as they get older they have developed expertise that the regular people will never achieve.
This isn't communist Russia. We don't gain anything by throttling the motivation of gifted kids except making the regular kids feel better about themselves.