Yes, we know that floppy disks and drives will wear out, and they have few if any sources for new repair parts. So the fact that the system is still more or less working today doesn't mean it isn't doomed and needs to be replaced before experiencing a catastrophic unrecoverable failure.
The point is it’s enough legroom to be reasonably cautious in the rollout rather than needing to get a big contractor to do a major and therefore expensive push.
