Nah, it's owned by the government. It's the government that decides whether they want to sell the land and it's the government that gets the money if they do so. Don't know how that could be defined as "owned by the King".

I guess people like to write articles that get shared on Facebook about the King owning 6 billion acres of land around the world or whatever, but the King doesn't actually own the land in any reasonable understanding of the concept of ownership.