Tesla, Honda, Nissan, Chevy, Fiat and Volkswagen have all produced cars with resistive heat in the past decade (not an exhaustive list, just a list that I could find on the first page of search results). So no, not an exclusively American thing.

Heat pumps are expensive, complex, prone to warranty claims, and subject to additional regulatory control (refrigerants). Resistive heating is cheap and simple.

I'm guessing that the development costs for a heat pump that is good enough for automotive use is well into 8 figures, and would probably take at least a year to fully test.

Given all those constraints, it makes a tremendous amount of sense that many cars were built with resistive heating.

I'm not going to say they're ubiquitous in the automotive world (assuming non-belt-driven like you mention below), but they're hardly brand new. The battery-electric buses in my city have heat pumps, and (IIRC) other cities opted for air conditioning in their trolley-bus fleet over a decade ago. Built to automotive standards is hardly uncharted waters.

Though perhaps I'm simply blown away living in a colder climate. Resistive heating if it's only to defog windows in the morning, or similarly rarely used, is reasonable. Resistive when getting started (one major hurdle, ICE -> EV, resistive -> heat pump, at a time) is reasonable. I just thought the automotive world had moved forward more rapidly than it had.

heat pumps are not magical technology. Pretty much every car sold in the West in the last three decades has one. There is only one reversing valve worth of difference between a standard auto AC and a heat pump.