I grew up in the 90s and I remember being able to truncate the year down to just 2 numbers when talking about years within the current millennium. It seems like we’re still saying twenty before every year and I’m just wondering when that will change.
IMHO when the two digit year equals the median age of all living people.
In other words, when the people who are born in 2xxx become the majority. That’s probably somewhere in the thirties.
(Not counting the ones who use a different year number, for example Chinese, Jews…)