That's not true from a mechanical perspective. Most SUVs use the same frame and parts as trucks by the same manufacturer (which is why they handle so poorly compared to sedans - it isn't just center of gravity)

If you define SUV as body-on-frame, sure. But most people think of crossovers as SUVs, and most are unibody. It's a big umbrella and how it's made isn't how mainstream thinks about buying.

By weight (gotta over-count those chevy suburbans, lol) that could be possible.

By number the median SUV is some sort of crossover or compact SUV built on a platform the OEM also builds sedans on.