When people say Gen Z are they talking about Gen Z in America or Gen Z on Earth? I notice many qualities ascribed to Gen Z seem to be completely alien to Gen Z

When people say Gen Z are they talking about Gen Z in America or Gen Z on Earth? I notice many qualities ascribed to Gen Z seem to be completely alien to Gen Z where I live which makes me suspect that these qualities are simply random variation and correlation hunting, and not inherent to that cohort’s formative experiences (smartphones, covid, etc).