As someone who's driven for nearly fifty years, and who's made a living at it for most of the last eight years, I have a couple of observations. Bear with me while I rant, okay?
Most people think they are “above average” drivers. Obviously half of them are wrong...maybe more, I was never very good at maths. People claim to be good drivers by pointing out that they've never had an accident. This means nothing. All it tells us is that other drivers have been good at avoiding being hit by them. Miracles do happen.
Everyone is Mario Andretti. And one thing you can never do is question another person's driving ability. They'll take it as a deeply personal insult. There is a strength of conviction that is almost religious in fervor.
Guys feel as if they own a certain amount of space in front of their car. God forbid that you violate this space (by, say, changing lanes and pulling in front of them). Instead of just slowing down and readjusting that following distance, they will demonstrate their displeasure by riding your bumper, honking their horn and/or other, more graphic gestures of anger.
On a boulevard (e.g. two lanes in each direction), a guy will dawdle along slowly in the left lane, blocking traffic. He may be focused on his phone, or lighting a joint or whatever, but he is oblivious to traffic around him. Until... Until an opening appears in the traffic and you try to pass him on the right. Then he will suddenly wake up, and it's “race-on!” Happens every time. Every time. Guys do not like to be passed. It's a masculinity thing. They think it's a threat or insult to let someone get over on them or get by them. Guys really are way too competitive, especially behind the wheel.
Which brings us to my pet peeve: Americans simply don't understand the concept of “keep right.” They don't realize that it applies everywhere, yes, even on roads that are not Interstate highways. And on those Interstates, people will doggedly plod along in the left lane, sanctimoniously believing that they're perfectly fine and legal as long as they're going the speed limit. Which is false. Nobody appointed you to be a traffic cop, a controller of vehicle speed other than your own. Just keep to the right and let those bastard law-breakers go by. Karma or the real police may catch up with them eventually, but it's not your call.
I could go on, but I won't. Driving for a living can be a frustrating experience until you learn to just let it go. For me, driving is not a competitive sport. If someone wants to go around or get ahead of me, I just let them. No big deal. It's not a race. Plus, I'm judged and rated on my driving now; too many dings for unsafe driving can get you permanently deactivated from Uber. And yeah, that happens.
I don't know where I fall on the good/bad driver scale, but I try to not make people who are riding with me feel like we're about to have an accident. And if you can make paying passengers feel safe, I guess that's got to count for something.