Well that's a technicality. There's no reason to base practical realities of Jan 1 2020 being the start of the "2020s" with the fact that Year 0 was missing.
> Those technicalities, however, don't change the fact that as a society, we seem to have collectively determined that decades begin in years ending in zero and end on years ending in nine.
I recall a CNN article recently about this: https://www.cnn.com/2019/12/21/us/when-does-the-decade-end-b...
> Those technicalities, however, don't change the fact that as a society, we seem to have collectively determined that decades begin in years ending in zero and end on years ending in nine.