As bad as the American problems are, they're largely First World ones. Parts of the US are as bad as Third World zones of disgrace, but the status quo in much of the US is where many real poor people in the rest of the world want to be.
Of course, we all face existential crises under our local conditions, because the existential predicament is universal (death, suffering, absurdity, alienation). I'm just saying we shouldn't overblow US politics. The governmental and culture war goings on could be sideshows compared to the rise of the Big Tech monopolies and other trends.
I don't like to predict what will happen because the available evidence is typically mixed and ambiguous. There are reasons to be pessimistic (global warming, etc), and reasons to be optimistic (our anomalous intelligence, technological advances). But it's anyone guess how everything will turn out in the long run.