Complex sentence: Skyscrapers used as hotels and as residential space are on the low side there are only a few supertall skyscrapers of that type in the 100 tallest skyscrapers in the world.
Split into simpler sentences: Skyscrapers used as hotels and as residential space are generally smaller. There are only a few super tall skyscrapers of that type among the 100 tallest skyscrapers in the world.