> Exactly. Farming on mars is not a problem worth solving
I know you're being flippant, but this is a textbook propositional fallacy. (Affirming a disjunct [1], I think.)
In summary, you argue: farming on Antarctica is difficult, so we import food instead. Farming on Mars is difficult, but we don't want to import food. Herego, we shouldn't farm on Mars or bother with it at all. Alternatively, if X (farming is difficult), Y (farm) or Z (import). You're arguing neither Y or Z by, implicitly, rejecting Z. That doesn't make sense.
So I would say that yes, farming on Mars is a problem worth solving, and one that will be solved once there's a need to do so (that doesn't mean it will be easy or inexpensive).
On Mars you have soil you can process into something plants can use (note: needs to be washed free of its perchlorate contamination first) whereas at the South Pole there is no soil that is not buried under hundreds of meters of ice. You can't just create a heated greenhouse on top of the ice because it will melt the ice underneath.
They've already done tests where they've grown plants in Martial soil simulant.
That you can't farm on. The farmable bits are in protected, heated shelters that are expensive to build and maintain.