This could just be about the scope you attach to a group. If the composition of the group changes is it still the same group? I feel most of the changes you me

This could just be about the scope you attach to a group. If the composition of the group changes is it still the same group? I feel most of the changes you mentioned saw a churn in the members of the groups themselves. Also, the article mentions changes can happen but not without a schism, which I feel most of your examples demonstrate that a schism is happening.