I’ve always been told the defining turn from boomers to Gen X was the end of the boom. Readily available birth control for men and women made family planning the norm. Gen X just doesn’t get a fancy name because they never got there “define with this” phenomena
That makes sense as a reason too. I think the 60s saw an undeniable cultural shift. The 80s is harder to pinpoint and yet I don’t know anyone born in the last years of the 70s that is comfortable with being grouped with Gen X without caveats.
i’m late gen x (78), that’s more comfortable to me than being lumped with millennials. (the caveat being, i suppose, that we’re dissimilar in some respects from early gen x.)
internet was not widely available until about the time i started college, and gen x media defined popular culture at that time. i also relate to the notion of being the child of two working parents - the first generation of latchkey kids.
i tend to see millennials as people who were kids when i was in school - and they grew up with the internet.