It will be a necessity if Musk plans to send people to Mars .... crawling around on the red planet would be so much of a buzz kill!
Mars gravity is 1 to 2.64 that of Earth. Loss of muscle mass is a bigger problem than just what it causes in terms of mobility. Months of PT to rebuild that muscle mass does not sound like fun. It is not that easy to build muscle in the first place.
This is another factor that makes me think Musk is rather inebriated if he thinks that he is going to get someone to Mars, safely, by 2022 or so. As I see it, if one thinks of humanity going to Mars as a problem, it is very complicated and involves factors well beyond just having a rocket that is capable of safely reaching Mars.
Why o why do we need to go to Mars??? there's nothing there? go to the moon instead ..learn from all your mistakes on the moon first.. Sigh and there's no hope in successfully terraforming Mars anyway no matter who says it ..unless we invent a planetary magnetosphere ...
Fortunately, I read something the other day that makes me think that Musk might have at least one brain cell - he stated something about going to the Moon before Mars.
When are we going to get it that Humans aren't meant to do space travel? We weren't designed for it. Our natural habitat is Earth, if we can't exist somewhere else without serious life support, special suits etc etc, whats the point?
Humans weren't meant to fly either yet look how far aeronautics has advanced. The point of going to space? To harvest an infinite amount of resources, to ensure the survival of the human race, to expand our territory, and to advance science. They are a billion reasons to go to space and only 1 not to go. "It's hard" sounds like an excuse for those without determination.
We also were not meant to swim, either and look how far we have come with that, too.
I have no problems with most of your reasons, however, when it comes to expanding our territory, I hope humanity finds a way to do so without infringing on the territories of other civilizations for any reason or in any fashion - although this aspect of space exploration is a long way off given humanity's current technology.
IF there is any merit to the idea that extra-terrestrial civilizations have been visiting Earth for millennia and those visits are behind various organized religions, I look at the resulting insanity by fanatics of all organized religions and wonder what the Earth might be like if we were left to develop on our own.
Plus, with planets now discovered in other galaxies, that pushes up the probability of life elsewhere as computed by Drake's equation. And with a greater probability of life elsewhere in the universe, we might just encounter a civilization millions or billions of years older than our own, not know it, and pay a dear price for encroaching on their territory and trying to claim it for humanity.
[EDIT] Here's the link for the discovery of planets in other galaxies for those interested -
https://phys.org/news/2018-02-astrophysicists-planets-extragalactic-galaxies-microlensing.html
Why should we go to Mars? Simple... We need to. Why? Because to ensure that the human race will survive past us blowing ourselves up. With the rate we're going we're going to have a Third World War soon and we need to ensure that humanity will survive that even if it means somewhere else.
Without viable means to ensure basic human needs, especially food, are met, if humanity destroys itself, any settlements within the solar system are likely to collapse because they will be dependent on Earth for survival. Even if there are viable means to survive, my bet is that settlements in the solar system will fail at some point if humanity destroys civilization on Earth. It will be a long, long time before settlements in the solar system are anywhere near the level of industrialization that Earth is - and thus, without Earth, living in a settlement in the solar system would be much like living in the stone age yet on a planet that which is inherently incapable of supporting human life.
