The real question is why are people waiting until their kids are teenagers to make aliyah. Why do we not encourage newlywed couples to move so we do not have this issue.
According to the Ramban and the Rambam-(at least according to most acharonim) there is a mitzvat deoraitta to live in Israel. Most people will not go down in ruchniyut if they live in Israel if they move to the right neighborhoods so back to the original question why are more religious Jews not moving to Israel???