As someone that moved to the US Midwest recently I can attest that firm suspensions are not the norm and seem not to be as popular here. Like you, I prefer them - better handling and better road feel.
However, after driving here for the better part of a year I can see why. I'm actually kinda cursing buying a sedan with stiff sports suspension here ... the roads are freaking AWFUL. They're mostly concrete (loud, with bumpy expansion joints) and have many cracks, ridges, potholes etc ... driving along many highways is like ba-dump, ba-dump, ba-dump constantly. Feels like my poor car will shake itself to bits.
At first I thought it was just shoddy construction, but then I took a work trip to some west coast states (Washington, Oregon) and the quality of the roads was better. Generally smooth, asphalt surfaces on the main highways, without cracks/joints. It was then I realised - it's a climate thing. In the Midwest the roads have to deal with temperature swings ranging from -40 C to +40 C in a given year, which is hell on the roads. I saw it with my own eyes this winter ... a previously good road near my house is now a terrible mess with ruptures and ridges and buckling all over it (we have had a harsh winter this year). Literally within the space of a week it went from "great" to "undriveable at more than 30 mph".
So yeah - I like firm cars too, but I wouldn't be surprised if they opt for squishier suspensions on average here in the States.