Those are outliers. Even within many of those subcultures, birthrates will fall over time. A few generations ago, Catholics in the US regularly had a dozen children. Not very common here now.
Why do you expect it to fall? Amish and Haredi Jews intentionally stay at arms length from wider society. They maintain strict social pressures that encourage their members to focus on children and discourage the dizzying alternative uses for time socially available to Catholics and the wider US population. Certainly in Israel the Haredi growth rate is remaining stable and has taken them from a marginal groups of a few tens of thousands up to one and a half million, 14% of the population.
Anyway say they do defy their customs and assimilate and follow suit, then other currently marginal groups that do find some way to keep birth rates propped up over time or raise them will eventually inherit the world. Not in our lifetime to be sure.
Those are outliers. Even within many of those subcultures, birthrates will fall over time. A few generations ago, Catholics in the US regularly had a dozen children. Not very common here now.
Why do you expect it to fall? Amish and Haredi Jews intentionally stay at arms length from wider society. They maintain strict social pressures that encourage their members to focus on children and discourage the dizzying alternative uses for time socially available to Catholics and the wider US population. Certainly in Israel the Haredi growth rate is remaining stable and has taken them from a marginal groups of a few tens of thousands up to one and a half million, 14% of the population.
Anyway say they do defy their customs and assimilate and follow suit, then other currently marginal groups that do find some way to keep birth rates propped up over time or raise them will eventually inherit the world. Not in our lifetime to be sure.