Well all the user knows is he will probably be poking around the man pages for a way to fix the problem.
So he will probably look on the tune2fs man page, which has helped him fix other problems in the past. And he will probably look at the mke2fs (-t ext4) man page, which probably was the program that "caused" the problem, many years ago. So these man pages should have a note at the bottom: "If you get any year 2038 warnings, it would be a good idea to just make a fresh new filesystem (thus with today's defaults), and copy the files to there." (My situation: a SD card formatted long ago on a long gone 32 byte system too perhaps.)
