Canadians buy diesels, always have, so there are many OEMs who offer a diesel motor here and not in the US model equivalent. When they do, at 1/10th population, they often sell more units to the Canadian market than the US one.
I remember driving the company 1990 Ford F250 in Minneapolis, where the owners lived during the winter.
We had to fill up at the high pressure pumps at truck stops, there were exactly two filling stations in Minneapolis/St Paul that had diesel on offer. I understand it's much better today, although it would not surprise me to learn there are still stations in the US that don't have diesel at the pump.
Back home in Canada, every single filling station, even back then, had diesel at the pump. Oh, and Ford didn't offer a diesel engine in the US models; we always had some kind of drama trying to get service at the dealership there.
You may see it as being common today to have diesel options in the US market, but the reality is it's not common today compared to virtually every market in the world, and that includes the Americas outside the US, it's just a bit more common in the US than it once was.