Either “Boredom: After some time you have seen basically everything.” or “Can’t keep up: The world changes so fast, and I’m, stuck in a mindset I acquired in 1543”.
And: Bureaucratic nightmare. “We have you on file as being born in 1924, but you don’t really look like a centennial. Can I see your passport instead of that of your great-grandfather, please?”
Actually, both.