I haven't listened to that podcast (long!), but I will comment anyways! I think Mearshiemer describes it well by the concept of the "unipolar moment" which lasted until 2017, where America was in the drivers seat and used it's position of power to try to bring the whole world into a peaceful democratic free-trade situation according to their own terms and norms, but somehow always excluding Russia because Russia was always "bad" and not recognizing that many other cultures disliked America's "norms" and were never sure about America's values, including free speech by the way.

So the BRICS are doing an end-run bypass around America's way of operating.

And I'm not personally concerned about a multi-polar world, or about America losing out, but I am concerned that America didn't champion it's own principles very well and so many countries out there have little respect for liberalism (including free speech) and will just steamroll the American world order, including the concepts of freedom.