This. You could just as easily swap "folders" for tandems, recumbents, trikes, e-bikes, IGH-equipped bikes, euro-style "Trekking" bikes, mini-velos, Omafiets, etc.

OTOH, USA is birthplace of the mtn bike, fatbike, cruiser, and probably some other stuff I'm forgetting.

What is nice is that there are a few specialty stores here and there which do carry a bigger variety of USA-oddball bikes. And I see more and more folders at regular bike shops -- not a huge array of brands, but at least a few floor models.