"So much was lost" is right!
Myself, I am convinced that there is no curve, from experiments others have done which I have been able to repeat. I think the "Azimuthal Equidistant" map may be the right one. East-to-west circumnavigation works on that map, since the north pole is in the center, and thus as you're traveling east, you end up making minor course corrections the entire way so that you end up going in a circle, returning to where you started from.
Never in the course of history has anybody done a north-to-south circumnavigation -- and that's an important data point!
I believe they haven't made a north to south navigation primarily due to how dangerous the north and south poles are to most forms of travel. There are also not easy refueling locations for those.