Are old-style paper driving licences still valid?

Old-style licences were replaced by photocards 23 years ago, but some people are still unsure whether or not their paper versions are legal.
The Sunday Times Driving Placeholder

Car Clinic: Why is the pass date on my driving licence...

I didn’t notice the error until I needed to hire a car, when the manager of the company seemed to think I was either lying or had been banned