In a lot of places in the US I get the feeling that you're tempting death if you want to go on a long ride. There seems to be very few good roads to ride on that don't also have heavy car traffic, because the entire infrastructure is much more recent and has pretty much been built exclusively around cars and trucks. For people who are dependent on cars and have to cover the costs and expenses that come with that, the bike becomes a luxury rather than a cheaper alternative.
This is very very regional, there is no rhyme or reason for cycling accessibility. Lots of Western states have extensive bike paths. California is a unicorn w all kinds of great bike riding. There are many communities in the US that have some protective measures in urban rides, sometimes it's just a painted line on the road. There are tens of thousands of miles in rural areas for fantastic riding.
Yes there are people who don't like to share the road with cyclists, it's better than @10-20 years ago but far from perfect.
An issue for all using the roads is personal electronics and onboard designed in electronics in vehicles. Vehicle manufacturers design dozens and dozens of things to be done in your car or truck besides driving!! I never needed to conduct an experiment about what will happen if drivers watch porn or movies while driving. I always had a good idea of what talking on the phone, or sending texts or videos while in the act of driving!!
Class is definitely an issue that is increasing year after year. Bike manufacturers are making money to enter the sport of cycling restrictive for many. For parents, having your son or daughter announce that they want to try bike racing maybe seen as a curse, especially if you see what Jr races currently look like, many kids,some pre teen have @$7000+ dollar bikes and thousands in clothing and accessories!!
Safe roads are only a part of the puzzle.