[Veedrac]

If we were to require but not have one leap second a year into perpetuity, it would take 1000 years to drift 1/4h off from true time.

That's 1000 years of more regular, workable time. And I'd hope in 1000 years people would have adjusted to the small offset.

Plus, one hour-big adjustment every 4000 years is certainly easier than 4000 second-long adjustments every year, if they really haven't gotten used to it by then. Note that 4000 years ago we hadn't an alphabet - no doubt we'll be thought of on equal footings.