a small proportion of people (both from bad vehicles and bad cyclists). Some observations:

Last weekend I rode my bike across the middle of the state of Nevada (from California to Utah) on highway 50, "The Loneliest Road in America." I rode 440 miles in 4 days, and had the time of my life. Even though the road is supposedly "lonely," I got passed by a LOT of cars. My general observation is that almost all people are really considerate in rural Nevada. 95% of the cars passed me in the far left lane...didn't matter of there was a double yellow, or a dotted center line, people gave me about 10 feet of space on average. Cars never really needed to slow down as they were so far away from me (although many did slow down just to be nice). Almost every time when people didn't give me a wide berth, it was because a car was oncoming, and the car behind me wasn't able to get over. In those cases, the car behind me often slowed down a bit, they scooted left a little, I scooted right as far as I could, and everything worked out. It felt safe for for me. Never really had a negative interaction with a car, and had a handful of oncoming cars gave me a honk and a cheer.

There are some times when it just isn't feasible for a cyclist to ride in on the shoulder of the road, such as poorly placed rumble strips or too much debris or too small or no bike lane.
Even going down a steep winding mountain hill, a cyclist might be able to average about the same speed as a vehicle (if a steep road has lots of tight corners), and it might be safer for cyclists to be in the lane, than trying to ride on a small shoulder with a rumble strip. Usually, even when I'm in the sorts of situations where I have to be outside of the bike lane, cars are often still considerate.

I've had maybe three really bad interactions with cars in the past few years. I ride a lot, so these are rare in some ways, but they are bothersome, especially when a motorist starts threating to run you over. Some people are just bad people. Rolling coal or a purposeful close passes and honks, when the cyclists is in the bike lane isn't cool. Yelling at cyclists who have to leave the bike lane for something legal like a left turn isn't cool. I think that cyclists should also be good citizens. They should yield, and stop when appropriate (though cyclists rolling through a stop might actually be allowed in your state, if they have "Idaho stop" cycling laws). Cyclists should follow the laws of the roads. My big conflicts as a cyclist have happened when following the laws of the road.

One last plug. Best purchase I ever made was a radar for my bike. I always know when a car is coming behind me, and it allows me to ride defensively, and also to be considerate. When a car is coming, my watch buzzes, my Garmin shows me someone is coming, and I can then react. What I usually do when I'm notified they are a few 100 yards back, is actually give my bike a little wobble (just enough of a wobble to let the car behind me consider if they really want to pass me closely), then I immediately move over as far right as is feasible. If I feel the buzz, and I don't have much space in the shoulder, or if there is an oncoming car (which might disallow the car in my lane to move over) I might take a quick look back to see if the car is aware of me, because I just really don't want to get hit. If you are a cyclists and don't have a radar, I'd look into it. Also, just an FYI, nowadays these radars take video, so if you are a bad player motorist, you'll likely be caught on video, eventually.