There are definitely confident cyclists who profess to be comfortable in some areas of the US. Ask them if they'd be comfortable with a relative who's 8 or 80 biking around independently in the same area and they usually become a lot less confident. Then look at what the actual data shows: how many people bike there? The numbers are nearly always dismal: even supposed cycling champion Portland has half Munich's numbers, and Munich isn't even trying very hard. Portland is quarter-assing things at best, and it goes rapidly downhill from there.

Or if you want something more concrete to work with: how many mile lanes of protected bike lanes or off-street bike paths are there in your town? How does that compare to the number of mile lanes for sidewalks or general vehicle lanes? What percentage of controlled intersections use a protected design? How wide are the roads? What's the speed limit, and how fast do people actually drive? How common are pedestrian islands? How sharp are the curb corners? How many of the painted bike lanes in the door zone? How common are walk/bike cut-throughs? What percentage of intersection lights have a marker for bikes?

Most cyclists who talk about how comfortable they are in the US don't realize just how bad it is there. Yes, you can still often get by; I certainly managed, in the bay area, and Seattle, and Utah, and even Alabama. But it was still total garbage compared to the places that take biking seriously (which is exactly why so few people do it in the states).

We live in an area that is, by most Americans' standards, fairly dense, and yet we started having our son bike to school a mile away, by himself, when he was 7, and he started biking alongside us to a kindergarten 2 miles away when he was 5. He's 8 now, and he sometimes bikes himself to a friend's house, or a park, or a grocery store or bakery for an errand. That kind of thing is almost unheard of in the US these days.

I realize how bad it is here, but I'm not really sure what you're suggesting? Throw up my hands and give up? Move to the Netherlands???

Some of the smaller American cities are also the best for bicycling. Davis and Madison come to mind. Most mid-sized or large cities are outright hellscapes, including most of the cities in the SF area and even most parts of SF itself. A good way to identify a decent bicycling city it to find demographic data on mode share and break it down by gender and age. If your bikers are all 25-year-old males, it’s probably not a great bike town.

Ann Arbor is a bit of an outlier in that as far as Michigan cities go, it's relatively bike-friendly. It's still remarkably suburban in most areas, though; good luck biking to a grocery store that isn't out in Pittsfield Township.

I don't live in Ann Arbor. This probably speaks to the number of bikeable college towns, though.

Biking is pretty routine in college towns. Assuming that's East Lansing or Ann Arbor, you probably have some 20k bike commuters. There is also a huge inventory of local used bikes to sustain the culture, and city councils will want to protect students and readily build bike lanes, especially if there had been accidents at tricky intersections. In other towns, not so much, and the absence is conspicuous both in seeing other riders on the road and the infrastructure to support biking.