Midsize SUVs generally provide a larger cabin and a larger road footprint than compact SUVs, but the difference is not simply an extra row of seats. Some midsize models devote their space to two roomy rows and cargo; others fit a third row into the same general size category. Compact SUVs usually prioritize a smaller package that is easier to place in everyday parking spaces.
The useful comparison is how each vehicle divides its dimensions among people, luggage, and mechanical components. Two SUVs with different size labels can overlap in rear-seat comfort or usable cargo room. Measure the areas you need rather than assuming every midsize model is more spacious in every direction.