"Homo economicus" is dead. Long live "homo tribuarius."
That's not really something to celebrate, but it's certainly true that in most democratic countries, economic self-interest is no longer the most important factor in voters' choices. Tribalism of various sorts is taking its place, and that is not an improvement.
Take three quite different countries that are all stalled in the middle of political transitions that would have been done and dusted in no time 20 years ago: Spain, Israel and the United Kingdom.