I'll have to give it a closer read later, but after skimming through, two things are on my mind: 1. This doesn't have to be and shouldn't be an either/or sort

I'll have to give it a closer read later, but after skimming through, two things are on my mind: 1. This doesn't have to be and shouldn't be an either/or sort of thing. There should be lots of people trying lots of different things, mars colonies included. Derailing people from what drives them is at best fruitless and at worst destructive. 2. The writer is too caught up on Mars specifically. The point is to kickstart spacefaring so we do it often enough to elevate our mastery to the same level we've achieved with so many other things. Mars is just the most reasonable vehicle for that. The mastery mentioned in #2 will eventually bring settlements and industry to dot the entire solar system, which reduces risk of extinction in the near-medium term to near zero and does a lot to prepare humanity for even further disasterproofing (e.g. construction of colossal generation ships and the like becomes feasible).