When I drive, I'm often looking for cycling conditions. Is there a shoulder? How wide are lanes? What kind of traffic is there? How much traffic? What speeds posted and actual? Is there any signage for bikes? Hills: grade, length?
Much of what I see is unattractive for cycling. So far, I've followed only one signed bicycle route: the Mississippi River route in western Kentucky. The way reminded me of cycling in Europe, with narrow lonely roads to funky or semi-charming little towns. No one was touring, though. Wheat harvest is underway, and lots of big farm trucks could be an issue.
Elsewhere, I've seen random "bicycle route" signs that are essentially meaningless. They stand alone with no directional help or points of interest.
The few cycling tourists I've seen were in the west. It's relatively good weather for cycling on reasonably good routes.
There were lots of road cyclists in Florida, men and women decked out in great kit befitting expensive bikes.
Since Florida, I've seen one grizzled dude on a bicycle, pulling a trailer. I think he might be a drifter. I've met a drifter or two on my cycling trips. I think mental illness played a part in sending those folks out on bicycles.
I chose not to bicycle this trip because 1) I didn't want to be gone 3 months, 2) many of the states are horrible for bicycling, and 3) I came home from our around the world trip overweight and out of shape. When I started to ride in the spring, I came down with an injury.
So here I am not riding. I miss parts of it, especially the accomplishments. I don't miss the heat, rain, headwinds, dogs, drivers, and sore body parts.
It's all a tradeoff.