The religion of the malcontents.
collectivists
Pretty much. Being part of a religion, a family and a community is a natural part of being human. We crave it and if it is removed from us we will attempt to build it anew.
But since, in this case, they are starting from scratch and ignoring the wisdom of those who came before they are unlikely to do a very good job.
So just tell them "Nihil curo de ista tua stulta superstitione". (I'm not interested in your dopey religious cult.)