It takes time for a solidly democratic country to screw itself up quite as badly as the US has done.
Also, the US situation was exacerbated by a number of factors unique to the US: "corporations are people", "money is speech", the two-party, first past the post voting system, the electoral college, and the specifics of the representation system, are all huge disadvantages for achieving good democratic outcomes.
Plus, I think there's a good chance that the more progressive European countries will learn from, and be inoculated by, the US mistakes. I didn't leave Europe for political reasons, I left for business reasons, so I don't have any serious concerns about returning.
Finally, I don't have very many decades left.
Why do you think so? Most developed and democratic countries are in trouble, lately. Instability is everywhere. T