5% of Americans take public transit to get to work. I wouldn't call that an almost certainty that you need a car. An almost certainty would be maybe under <.001%
If there was a 5% the market would crash 50% tomorrow. Would you call that an almost certainty that it wouldn't happen? You wouldn't hedge your risk? If there was a 5% that you would die tomorrow, you wouldn't feel concerned?
What are you talking about? If 5% of the workforce showed up tomorrow, what do you think would happen? How'd you feel if you had a 5% chance of having transport to work?
5% is "huge" when considering probability of a "catastrophic" event compounded over time, because what you're really thinking of is "expected value over a year" or something like that. This 5 percent, by contrast, is a fraction of a population.
For example: There's a 95% chance I forgot about my tea and it ended up cold. We now ask "Do you expect my tea to be cold?" and can ask "On a scale of not certain to very certain, how certain are you?" I'm very certain my tea is cold. Now to forget it in the microwave.
I'm wealthy enough to live in a place where commuting by public transit is practical. I should move to a car-only distance to save money, but end up spending it on the luxury of convenience.
This is America. So the answer is almost certainly: "Yes, you need your car to reach work."