Your arguments would work just as well against going to the moon. For being nerds it sounds like your friend circle was more on the finance side thinking in terms of projected returns rather than exploratory adventures.
I believe eventually we will be on the moon again, and on Mars, but it will require a lot more technical progress before the cost-benefit analysis makes sense. Or maybe all we need is a second cold war, with murderous dictators propped up around the world, CIA toppling governments, proxy wars killing millions, that kind of thing. Choose your pick.
Figuring out how to live on Mars mostly involves solving Mars specific problems. It’s close enough to the sun you can just use solar panels, enough gravity to avoid most zero g problems, there’s an actual atmosphere to extract oxygen and carbon from, minimal need for deltaV, etc etc.