[cosmic_cheese]

I would be extremely surprised if it's insurmountable. It may turn out that this effect is triggered by environmental factors that are entirely controllable that we simply never had any reason to control.

There are so many unknowns when it comes to crewed space travel and habitation that it's difficult to say much of anything with certainty.

[nine_k]

Crewed sea travel should offer many hints. Its history is many centuries long.