That doesn't seem right to me. A person driving 10K a year will hit 300,000 miles over the course of 30 years. Does the average person really have less than 1 accident every 30 years? Especially when they are younger?

Per mile is a pretty poor measure. My dad drives at least 40K/year (long commute) and has averaged one accident per 20 years - but obviously for a regular driver following a familiar route the chances of an accident are pretty low. I would expect someone who drives less would actually have more accidents/year.

Mentally reviewing the people I'm close to, the figure seems to be off by at least an order of magnitude.

I think it includes truckers who are far safer than normal drivers on average and do a lot of driving.

I put 40k on my first car and hit stuff enough to warrant replacing something - often just a fender etc - at least 5 times. Only one fender bender when I rear ended someone at ~15 mph talking on my phone like an asshole.

I know I'm a worse driver than most. But I also wouldn't say that my similarly young friends average anywhere close to 1 such error per 250k miles. Definitely closer 25k.