So default-mode democracy wins in a walk.
This was not true before the 18th century. But before about 6000 years ago there were hundreds of thousands of years of pre-history when all humans lived as equals, reaching their decisions by discussion and consensus, in little hunter-gatherer bands.
We know this because some of those bands, living in out-of-the-way places, survived long enough for anthropologists to study them — and they were all egalitarian. In fact, they had no formal leaders, and the worst social crime was for one adult man to give an order to another.
They didn't hold elections, because the bands were hardly ever more than a hundred strong and they could just talk things over. But the core belief of democracy is that everybody has equal rights including a share in the decision-making process, and our distant ancestors all believed that. They believed it for so long that it became a basic human value.
That basic human belief went underground when the first mass societies appeared around 6000 years ago. The only way to run them was from the top down, by force, because without mass communications (they hadn't even invented writing yet) there was no way for tens or hundreds of thousands of people to make decisions together as equals.
So the tyrants took over and had a very long run, but the belief in equality never died, as all the slave and peasant revolts attest. And by the 18th century a kind of mass communications had finally emerged. Just the printing press plus mass literacy, but that meant everybody could get back to making decisions together as equals, and so the democratic revolutions began.
The United States was the first, perhaps because it then had the highest rate of literacy in the world. The far more radical French Revolution came only 13 years later (it even abolished slavery), and democracy just kept spreading. Half the governments on the planet are genuinely elected now, and the other half pretend to be.
Democracy has nothing to do with being American or “Western”. China was the first country with printing, and if it had also had mass literacy it could well have been the first country to have a democratic revolution. American democracy will probably survive its current difficulties. Democracy as the default mode in the world certainly will.