Some food for thought (and beautiful images of Mars), although I think the technical feasibility will make a big jump if SpaceX’s Starship will successfully launch this year. Ultimately I agree that it makes little sense to send humans to space for research purposes.

However, what might make sense is to do robotic resource extraction in the asteroid belt. Mars is kind of a natural stop on the way there AFAIK. If that turns out to be feasible, there will be probably some human piggy-backing on these robotic shuttles. I would guess we will see some elderly and relatively rich people drive this human exploration as some sort of extreme sport (due to low gravity it is doable by elderly persons) with no real expectation to come away unharmed (or necessarily return at all). But over time this will build up sufficient experience and infrastructure to make a Martian colony feasible and since the robotic shuttles going to the asteroid belt will be mostly empty on the way there, getting supplies to this Mars colony will be relatively cheap.