My concern is the same as yours kuu. If that happens in one year, what on earth could be the consequences of spending decades in space?
I bring this up as a limitation, because it was, at least for me, something I never would have thought could produce such a drastic change on someone. Astronauts are basically the healthiest people on earth. If they have problems after a year and they can handle stress well... I think you can see why it would be a limitation. As a consequence, It seems my prediction that if/when we become a multi-planet species, all the well off have more opportunity to go off into space and earth is left with the rejects... so to speak. I don't think such a premise would be good for the earth, as well as its creatures with the people living on earth who are simply not as superior as those who would get the opportunity to live amongst the superior.
I have long thought that humans have recently had an exponential growth in understanding since the industrial revolution because the collective unconscious knows the earth is about to go into complete catastrophe.