The coupling between climate and sea ice is more complex in the southern polar regions, and the increase in sea ice there is also likely to be an artifact of global warming. But this may explain why a global chart doesn't show the sharp decrease you'd expect.
Was there anyone predicting in the 1980s or 1990s that with global warming arctic ice would decline while antarctic ice would increase? Was anyone predicting this before the observation occurred? How do I know that the idea that global warming causes an increase in southern ice is not just an after the fact rationalization?
What I find more alarming are folks like yourself that have so little respect for science that they think there is potentially some cover up of the truth.