I'm not confused. I just think it's hilarious to present "dozens of miles" as if it were a lot. I make no comment on the correctness of the quantity built.
Well, I know in my development specifically we built about 40 miles of paved bike trail. The neighboring developments all have connecting trails of similar size.
It all connects into the regional bike trail system which includes a 50 mile paved and marked trail that gets you literally from farmland into the major city and crosses through almost every other sizable city and employment center along the way, each with connecting bike systems of their own. I don't know for my county specifically but the neighboring county has something like 500 miles of paved bike trail. I'm pretty sure my county isn't quite that extensive or well integrated but it's almost all fairly new, within the last 20 years.
It doesn't bring every town to within a friendly bike ride, but if you live and work near the 50 mile main trail, it's reasonable to bike commute to work every day.
The whole system across 3 counties and about 3 million people is something like 20 times the size of Copenhagen's to put it into perspective. It's just that my taxes mostly cover my local area and we're probably at under 100 miles of trail all told or about half what all of NYC has.
I don't know if that's a lot or not. It's not a mirror of the road system in terms of size (which I'd personally like to change), but it's no slouch either.
How many thousands of miles of streets do you have locally?