I think Kumari can't touch the ground or maybe I'm thinking of something else. Is there any reason they keep the golden child suspended?
Or is it just easiest for them that way in order to keep him from touching them?
He can clearly touch the ground because he is shown running with Murphy's character toward the end of the movie.
I got the impression he was kept off the ground in captivity so he couldn't use his power to effect positive change in anyone in the room with him. Remember, he just had to put a finger on the one bad guy and his whole demeanor (and goal) changed toward helping the Golden Child. He probably could have effected everyone that way if he could have reached the ground or been directly on the ground.
"Get busy living, or get busy dying." Andy (The Shawshank Redemption)