Generations share a "core" of experiences that happen during some of the most impactful years of their lives. First geopolitical event I remember was 9/11. For some it was the Great Recession or COVID. Those big events end up exerting a lot of influence on age groups.
I think Generations can be overused in the sense that it's used like a monolith when it's not. The clickbaity "Generation Z doesn't want to work" is actually the less clickbaity "Many in Generation Z find working a less attractive option because of these specific shared experience/values..."
My (parents’) CompuServe and (due to living in the Central Valley but most of the BBS’s I had info on being in the Bay) phone bills fron the 1980s tell a very different story.
My family didn't have internet until around 1998