I mean people have run the math and you can certainly travel to and from mars while receiving a low enough radiation dose. I envision in our lifetimes a Mars similar to the Antarctic bases at best: a few scientific stations manned by researchers and support staff but no permanent settlers. That’s certainly an achievable bar regardless of if the more science fiction stuff isn’t yet. I suspect that people like you will be saying this is foolish and impossible all the way up until the day the Starships start landing…