The best argument for democracies, are their possibility of peaceful revolutios and this problem might become very relevant for china too.

You can compare the early US with present china. Both countries had/have great potential for economic growth, and everything went well for its citizens as long as the pie got bigger. The interests of the elites and the working class were aligned by that. Once the interests of these two groups diverge, democracies become relevant again. That's why the tech oligarchs are so afraid and politically engaged, to distract us with the have-nots below us.

Today, china just has the better aligning plan, while the west is struggling to keep it's democracies. IMO any reasonable trajectory for sustainability and social stability is a contradiction to western elites, who cannot think outside their status quo, while china just builds it. I really wish china well and that they dont develop such an arrogant international stance like the west.