I strongly disagree with what you just posted.I elucidated upon the points in the second post.
I got your point. My point is that everything that needs to be tested, except for gravity, can be tested on Earth a great deal safer, faster, and a lot less expensive than on the Moon. For potentially fatal situations, a few minutes on Earth is several orders of magnitude better than 4 days to the Moon, and even that is assuming a suitable spacecraft is sitting and ready on the launch pad.
A large enclosure with controllable changing light and temperature can simulate those aspects of Mars, and a lot more accurately than anything on the Moon. Simply preparing something for a harsher environment does not translate to preparing for the eventual working environment.
You said, " makes a better test bed than Mars", but no one is suggesting using Mars as a test bed for Mars.
We already have the technology for long term habitation and survival off-Earth.
As for alien bacteria or other infectious microbes, it is highly unlikely there would be any on Mars. All of the infectious tiny wildlife here are based upon our DNA and were adapted to interact physiologically with our biological systems. There is no reason to believe that any alien microbes would be dangerous to us. The concept that they would be deadly to us is strictly a baseless Science Fiction construct.
You seem to be dangerously naive about some realistic hazards.
Of course the survival technologies will be developed as much as we can do so here on Earth before trying them on the Moon. But, to suggest that we will get everything right with how to extract resources from the Moon itself without being there and actually doing it is dangerously over-confident. And, I doubt we can fully simulate the problems with Moon dust here on Earth, especially with our current state of knowledge about how it behaves on the Moon's surface, naturally.
As for life on Mars (if it exists) not being capable of being fatal to humans - that is pure wishful thinking. It is our own immune systems that have to adapt to defend our life processes against infection by other organisms. Yes, there is a current status to a long-term infection vs immune systems conflict here on Earth that is specific to the evolved biologies of both the infecting and the infected organisms. But, as demonstrated by the recent COVID infection, just an immune system over-reaction to a "novel" infecting agent can cause fatalities in humans. And, there is also real potential for a novel infecting agent from a different world to simply use our bodies as a resource without our immune systems having any features that can effectively combat it. Plus, there are plenty of disease-inducing organisms here on Earth that humans are still trying to develop specialized medicines to combat. Just because Hollywood uses some of these concepts to motivate fictional plots does not make all of these possible hazards fictitious.
You seem to be dangerously naive about some realistic hazards.