Obviously with autocrats this isn’t applicable but there’s nothing inherently nonsensical or inexplicable about why mostly old dudes rule much of the world.
I don't think that holds as an explanation given that 1. there's not a lot of wisdom going around among the geriatric leaders of the world, 2. this is a pretty rapidly increasing trend, not some fact of history.
Historical leaders used to be younger, including after accounting for increased lifespans. Just look at the founding of the American Republic. It's much more a sign of two things. Increased decadence and civilizations that are themselves at the end of their rope, and in democracies in particular a geriatric population that keeps voting itself into power based on their own interests.
Also you can’t really talk about a geriatric population ‘voting itself into power’ if it makes up such a small proportion of the population. Young people just abstain from voting in western democracies, which is a choice just as much as voting one way or the other is. Yes, a person votes in his own self interest - that’s how that works.
You’re not really supposed to just vote in your self-interest. It’s a proxy for violence.
No, that's not how that works, some Rousseau might be in order. What early Republicans still recognized is the concept of General Will. That a polity is not just the sum of its individual interests but requires an orientation of each member towards the shared common good. A democracy that is governed by self interest, in which simply put each vote is bought is a democracy in decayed state.
That this doesn't even register with people any more and is perceived as the norm is exactly what I'm talking about when I'm saying that most current democratic nations are at the end of their life. If young people are a demographic minority and each person votes only in their selfish interest the future of the nation is, by definition, dead.That they opt out in that situation is actually rational.