A lot of things factor into this:
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Space and marketing. The US is huge and its infrastructure was largely developed around large sedans from the 50’s-70’s. People have the space for SUVs and auto companies have HUGE margins on them so they market them hard.
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They serve as an almost 1 to 1 replacement for the high riding, spacious, land yachts that many in the US grew up around. This was pointed out in a post on /r/cars a month or two ago and makes perfect sense. People in the US largely grew up with vehicles that had a lot of interior space. Packing the a bunch of individuals into the car and going on a week long road trip was common place for a lot of middle class America for many years. As safety regulations became more strict vehicle body panels became thicker and encroached in this prized interior space. Minivans and then SUV/ Crossovers offered a solution to this.
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Ease of access and loading. The higher seating makes getting in/ out of the car and loading/ unloading much easier. For anyone who has mobility challenges the convenience is either the extra cost.
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Young people never want to own the cars their parents owned. Those whose parents owned large sedans bought wagons. Their kids hate wagons, when they grew up they got minivans. Their kids hate minivans, when they grew up they got SUVs. Their kids hate SUVs, when they grew up they got crossovers. Who knows what’s next?
100% this was the progression in the US:
Large sedan -> wagon -> minivan -> SUV -> crossover