The ISS has a lot of doohickeys hanging off it, so the cross section is going to be much larger than if the ISS was condensed into a sphere or cube. The ISS is

The ISS has a lot of doohickeys hanging off it, so the cross section is going to be much larger than if the ISS was condensed into a sphere or cube. The ISS is also a lot less dense than most satellites, so even if the drag were the same it would have more of an impact