I... don't know. The Dreamscapes are One's own, even though Sleep clearly has power here of some kind. I'm not sure if the original intention was for him to bring those of us like him to Sleep or if it's more of an unintentional consequence. He mentioned he can't control some kind of force that's inside of him, and because of that, we dream with him.

He runs the Dreamscape, but I don't think he's in that much control. The Abomination ultimately killed him, that's how the dream broke apart and set us free.