An incredibly small market given the cost of getting a human to the moon and keeping them there. There will be no economy of scale here for quite a while so this is an unlikely driver of any revenue. Tourism is barely a thing for orbital trips and not even close to being sustainable for such a small energy expenditure compared to a lunar visit.
> (2) Entertainment industry–reality TV shows filmed on the moon.
Never going to happen. Chicken-egg problem here and a complete fantasy.
> (3) Professional sports
So rediculous it does not even rise to the level of fantasy.
> (4) Oh no, China's lunar base is bigger than ours,
Possible, but not quite the national motivation it was in the midst of the space race. In the 60s and 70s existential conflict with a competing super-power could barely get flags and footprints on the moon. What passes for modern nationalism is not enough to sustain a lunar presence.
> (5) Scientific research
This is the most likely of any options presented so far, but is still completely reliant upon the government teat to drive action. This is the exact same revenue model we have now and mining government contracts and lobbiest-driven funding is not exactly fertile ground for a 'gold rush.'
The point remains that there is no revenue model at all for this, no is there likely to be one within our lifetimes.