It seems like it’d get increasingly impractical as the years go on to hundreds of thousands and millions of years to write them out that way, but then…I guess technically one may already do this with the preceding years, so future’s fair game for it?
It would make more sense to switch to a calendar with a different year 0. Like when human civilization started, which would make.the current year to 12k+. Or when earth started, which revolutions around the sun we are counting. Which would make the current year something with 4.5 billion.