Well, leap seconds are going away, so we don't.

They were never adequate for the long-term anyway, as the "two leap seconds a year" scheme will break down as the earth's rotation slows over the centuries and more and more leap seconds will be needed.

We're talking about an hour time drift over a few thousand years. Does that really matter? It's like caring what Julius Caesar's sense of "morning" or "evening" was. They never really solved any practical problem.