There is no reason for humans to ever return to the moon. The cost and risks are not justified. Drones and robots can do anything that needs to be done. They don’t need to breathe, they don’t need to sleep, or eat.
I mean, there wasn't really a "reason" to go to the moon in the 60's either. I think I more or less agree with JFK on this:
"Many years ago the great British explorer George Mallory, who was to die on Mount Everest, was asked why did he want to climb it. He said, 'Because it is there'. Well, space is there, and we’re going to climb it"
I could try and find a lot of justifications about medical research or something, and those might be cool, but it would be dishonest if I pitched those as a "reason" to go, because I would want us to return even if those reasons weren't there.
Today people still do it, but it means nothing to anyone other than those people.
Going to the moon in the 60s was an impressive feat. It pushed the boundary forward. But that's all it did. There's literally nothing of value there.
Sure most of the people who saw that are dead, or will be in the next 20 years. So it will seem "cool" to the next generation. But selling "cool" to a congressional appropriations committee is a tough sell.
We aren't gonna colonize the moon (or indeed mars) because frankly it would be too expensive, and there's no point. There literally is nothing to gain from a colony in either place, and there's no way to fund it (and no reason to fund it.)
ISRU water to hydrolox to reduce amount of uplift from earth's gravity well?
The moon lacks too much to be self sustainable. Mars is a stretch: it is likely someone will reply that mars isn't possible and they will have good points, so while I have concluded it is just possible I can see the points of those who think it is not.
Imagine if we never built ISS because putting a space station in Earth's orbit was a solved problem...
Imagine stepping outside into a world where absolutely everything is coated in dark gray copy toner that gets ingrained into all that touches it.
I don’t think I could do it due to the anxiety.
The dust would give me some anxiety too but I think it would be worth it.
The relative costs are flipped for putting a human on Mars/moon - the robot is cheaper.