While I agree with your general point, pretty much every rural area is exactly like this, including where I work in South Carolina. If I were to ride my bike to work I would be solely going on 45/55 mph roads. Most roads are one lane each direction with blind corners and easy opportunities for people to speed due to lack of traffic and cops (something I even do admittedly, but make sure to stay within the lines at all times). There is no option to cut through slow neighborhood roads since this is a rural area. Sidewalks do not exist but walking would be relatively safe far off the shoulder.
Yes to this!!! I suspect that I live not too far from you, and it's the same way here. I cannot safely bike anywhere useful from my house. Once I leave my quiet neighborhood road, I'm on a 2-lane curvy road with a 45-mph speed limit and people who frequently drive faster. (A car probably goes by every 30-45 seconds, depending on time of day.... so not a busy road, but not a super-quiet road either.) That actually wouldn't be too awful for biking... and I do run/walk along that road sometimes for fun. To get anywhere practical, though? I'd either have to turn left from my street, go to the end of the okay-ish road, and pull onto a 2-lane 55 mph road that has tons of traffic (not uncommon to have to wait a full 2-3 minutes to make a turn onto that road, even a right turn) and zero shoulder.... meaning that I'd slow down a long line of traffic behind me, assuming they saw me and DID slow down! Alternatively, I could turn right onto the okay-ish road, ride to that end of the road, get on another okay-ish road, and that road (whether I turned right or left) would eventually take me to a different 55 mph highway. Rural areas aren't like cities... there isn't a network of connected streets where you can just jump to a different road. All of the side roads that come off the main highways in my area are dead-ends... there aren't any interconnected neighborhoods.
I could move, I guess. (Well, not really at the moment for various reasons, but let's say I could.) There actually is a small neighborhood right behind behind where I work, so living in there would allow me to walk/bike to work. That would be great, but going anywhere else we would need to go would require pulling out onto an even bigger highway.... a 4-lane divided highway with a 65 mph speed limit (traffic typically moving at 70-75) that's heavily traveled by tractor trailers and lots of car traffic. So I'd be moving to bike to work, which would be helpful, but we would still need to drive for any errands/entertainment/etc, my husband would have to drive to his job, etc.
I went to college & vet school in Gainesville, FL and biked everywhere during those years. It was a college town, so people expected to encounter people on bikes. I could find roads that weren't too bad by changing my route up a bit. It was great. When I lived in Sarasota, FL, same thing - it isn't considered a very bike-friendly town, but I never had any trouble because the streets are connected in a grid and it was easy to find a route that wasn't awful. It was great and I loved it. I hope to someday live in an area like that again.... but it's not in the cards for me right now.
Anyway, biking is great for many people but it isn't realistic everywhere. It may very well have been realistic for the guy in the original story, but I think it's unreasonable to say that it's realistic for everyone in every area.
Also, someone else (can't find the quote right now) commented that rural roads can be good for cycling. I think that's entirely dependent on the local culture. I have a friend who lives in Utah who bikes on rural roads all the time. Here in my part of NC, though, a good portion of the car traffic is jacked-up pickup trucks with Confederate flags on flagpoles mounted to their trucks... those types of individuals aren't usually too friendly towards bike traffic.