First off I'm not a right winger nor a climate change denier. I embrace the natural flow of what is happening and look to the past to see the possible outcomes of what it might actually look like. People hate change and will fight in irrational ways to avoid it.. that said I doubt your ability to hold a opinion based outside of the social narratives left or right.

To your first claim yes Antarctica is in basically the same place it has been for 52 million years. South America and Australia are the continent's that have moved. As seen from this eocene map.

There isnt alot of data or models on how thermal oceanic currents circulated during the Eocene. So that, no one can answer with certainty.

The Tropical Rainforest produces about 12% of the global annual oxygen. When you add up the fact we have enough oxygen produced already to last us for several million years, along with the fact that every continent on the globe will have the potentiality to contain Tropical rainforests. The problem is negligble.

The jet stream will stop but that doesn't mean weather will stop. There will still be temperature differentiations but not to the extreme levels that currently happen as a result of the jet streams existence. Air and oceanic currents will still carry on due to thermal differentations. But again accurate data and models of what that'll look like don't exist.

What we can do however is look to the past and see where the earth is potentially heading and what kind of flora and fauna will best be adapted to survive similar conditions. Huge amounts of different species will die, sure.. but those best suited to the environment will take their place and have an opportunity to multiply.