I think part of it's that "SUV" better refers to the shape of the car than the size. Same for vans. I've got less experience with minivans, but I'll assume they're similar.

I bought my SUV because it was more fuel efficient and only slightly larger than my old hatchback. But I don't have something like a suburban or whatever.

When I hear "van", I think

Most minivans are roughly the same, but with windows and shorter. (Again, in my experience)

Most of the SUVs I see are what I think would be called "compact crossovers", so that's what I assumed was meant when OP said "kids, cargo and bike carrier".

Suv I think they meant:

Minivan I picture:

Suv I think you picture: