It tells us something, just not something anyone seriously wondered about. We can be pretty sure that vehicles with touchscreens don't get into (for example) 10,000x as many accidents as vehicles with manual controls, as that should be visible in the statistics.
What it doesn't tell us is whether or not touchscreens pose any significant additional danger.
There's a lot of factors that go into reducing auto accidents, so that correlation doesn't really tell us anything about the danger of driving with touch screens in the car.