I wonder if that's because more recent periods are considered in more detail - both for granularity and as a complex period. Whereas the further back you go, th

I wonder if that's because more recent periods are considered in more detail - both for granularity and as a complex period. Whereas the further back you go, the more they get grouped together and simplified into stories. "The 80s" (1 decade) is considered in more detail than "the interwar period" (20ish years), which is considered in more detail than "The victorian era" (70 years) which is considered in more detail than the Renaissance (200 years) which is considered in more detail than "Late antiquity" (500 years). I suspect in 2100, not very many people will be talking about the 1980s in great detail, and if the term 20s is used will refer to the current decade