You are refuting your own video.
The casinos make the infrastructure valuable.
Without the casinos Las Vegas would be an economic hole. It would rapidly become a ghost town and no amount of levying land taxes would give the people jobs.
Look at any small town with a big employer to see the effect of that employer leaving. By your argument the prosperity of the town should go up when the employer leaves, because they are no longer stealing all the value in the land for themselves, they are just leaving it there for the community.