Look, if a 300 pound (american) football player crashes into a 175 pound player, who is going to get more hurt?

No one is arguing about that, all other things being equal if a heavy thing hits a light thing then the light thing is going to come off worse.

But in the case of SUVs vs. mid/large cars all other things aren't equal. The basic design of modern cars differs from that of SUVs.

An SUV may well end up with less damage to it in an accident than a car. But that isn't generally a good thing for the person inside. Well designed, modern cars are designed to have a solid, stiff passenger shell with easily deformable stuff around it. That way the deformable parts of the car soak up the energy, rather than the soft human slamming into the hard inside of the hard car and taking the damage.

Most of these huge SUVs are not designed this way, they take a heavy chassis and stick a body on the top. A very different approach, they don't have the same monocoque design that modern cars do.

Many of the latest European SUVs now take the same approach as the cars do and therefore bahave similar ways in crashes. They still have some of the problem of being a menace to other smaller road users though, due to the height of their bumpers.