It is true. At night a 70-year-old person is basically blind. They can't cope with oncoming headlights because their pupils take seriously minutes to make adjustments that a young eye can make in seconds. Old pupils don't open as wide as young pupils. Old eyes have only half the rod receptors a young eye has. These effects are already noticeable to people at age 50.

The elderly can only drive safely under ideal conditions: sun high, not on the horizon, not at night, in clear weather where nobody is using their headlights.