Personally, I'm excited to see what kind of biomes end up emerging on a melting/melted Antartica.

Well ok, even I'm not pessimistic enough to think I'll live to see that, in a way that its dramatically different than it is now, but hey, its like uh... a subbranch of speculative evolution, sorta.

Maybe in a 100-200 years we have enough glacial loss and icemelt that West Antarctica might have parts where actual soil is regularly facing the sun.

I think this is a 'what if all the ice was gone' map:

"Most of us" is not "all of us". Humanity will survive and the survivors will adapt.

Nothing but positivity here.

That's not how that works. The Sahara savannah is tied to the rotation of the earth on its axis. That takes roughly 23,000 years. The period of time between savannah periods is about 13,000 years and the last one ended roughly 6,000-7,000 years ago. The next one will start in roughly 6,0000-7,000 more years.

It will be, like, an oasis for us in the future!