I think there is a little bit of truth to both sides. I think most people are closer to the middle than the extremes but in cases like this, adrenaline is flowing and emotions are mostly reactory without much thought.
Recently I have been priveledged with 1st hand information of what actually goes through the mind of drivers as they approach cyclist on the road.
About 2 weeks ago my wife and I were out on a ride, headed through our little downtown area back home. On the main road which we were riding (20mph speed limit) there is a large 6' paved parking/bike lane which we were riding in at about 15mph. There may have been 1 car parked in the 1/2 mile stretch of roads.
Unbeknownst to us, our daughter (13) was being driven home by friends of the family with which she stayed the night. She informed us that the dad (whom knows us and we are friends with) upon seeing us on the road as cyclists (had no idea it was my wife and I) started complaining about cyclist on the road and slowing down all the traffic... etc. At that point my daughter spoke up and told him who it was. She said that his wife laid into him about talking like that and keeping his mouth shut.
Anyways theres some insight from the mind of a typical American driver.
At my age with 4 kids still at home, I tend to ride very conservative these days. Long gone are the sprints from light to light in city traffic drafting off the car in front of you. I no longer assume right of way, to the point of going around the back of a car at a stop if they havent made eye contact with me.
It never hurts to wave and say thank you for cars that stop or wait to let you pass. A little bit of gratefulness goes a long way.
As far as the OPs experience, it sounds like typical American Suburbia. Everyones looking out for themselves and no one is sharing. If you have seen the inside of the house of more than 5 people on your street/apartment building your doing a great job of building community. Without that community you are on your own.
-Sean