I'm not convinced about 1. There are a lot of things we could be doing about a 9/11's worth of dead people every single month that we just don't.
In any case, it's a good barometer for judging personal risk. I don't stress about the danger when I get into my car, so I probably shouldn't stress about the danger from something substantially less likely to take me out. It contextualizes a number by comparing it to something most of us do every day.
I think a lot of people sort of instinctively avoid thinking about or engaging with the dangers posed by cars, at least in part because it creates a sense of dissonance that there’s a non-zero risk of life changing harm to you or your family from such a “normal” activity. For many people today, there is no alternative but to accept the risk if you want to do anything outside your home, other than dramatically upending your life to move somewhere else. Thinking too much about risks that feel outside your control just creates a state of anxiety.