Willingly moving into apartheid is a terrible idea.
It is autonomy, not apartheid. There are many ethnic/religious communities around the world who have fought for autonomy to varying degrees of success.
Also it's been done before https://en.wikipedia.org/wiki/Aboriginal_reserve
Autonomy is the best way to preserve culture. A tiny minority living among people who do not share their values will eventually lose any connection to their past due to assimilation unless they adopt extreme orthodoxy like the Amish/Mennonites/Haredim (who too have to form ghettos to achieve their goals).