Why don’t Formula 1 cars have airbags

Because F1 and the drivers have other safety mechanisms that are better suited than airbags to the task at hand. There’s no chance in an F1 car that the driver is flung out unless the car itself has totally disintegrated; and even so, he’s in the survival cell of the F1 car.

For starters, drivers wear helmets; but more than helmets, they wear what is called a HANS device (a head and neck support). This sits on their shoulders and prevents potentially fatal Basilar skull fractures.

In addition, instead of your three-point seat belt, they likely have a five-point harness.

All of these mean that there’s no chance the driver’s head will hit the front of the car (the primary purpose of airbags). Furthermore, the driver sits in a survival cell that is designed to be rigid in the event of a crash.