The first is whether or not the US is unique in having something of a gerontocracy. If so, why?
This is an interesting question that I really wanted to address. Pew did an article on this, and it seems America may not be unique, but it is unusual. Biden is in the top 5% of world leaders in age, and countries that are considered freer usually have younger leaders than those that are less free. I'm not familiar with the Cameroonian government, but I suspect Paul Biya is not surrounded by other 91-year olds either.
As for why, President Johnson raises an interesting point earlier in this thread about Gen Xers not being able to beat these people, and with Ramaswamy I would add Millennials at this point too. There have been younger candidates, but they don't beat the elders. Some of these elderly leaders like McConnell and Pelosi are protected by heavily skewed constituencies that allow their party to protect them. But it is quite striking that Trump and Biden were able to easily weather age-based concerns and I think that points to a legitimate issue with candidate quality among Gen X and Millennial politicians. Why that issue might exist and why it might be worse here than elsewhere, I'm not sure and I would be interested to hear others' thoughts on that.Old isn't always old though. You seem to like to attack Pelosi, but I'd say most of us would be fortunate to have the stamina that she does at her age. She certainly doesn't seem to be the age that she is. However, when considering a society to be a gerontocracy, it is worth keeping in mind that not only does every individual age differently, but men tend to age a bit faster compared to women. Pelosi's district is a natural constituency no matter how you try to set the rules. McConnell is of the Senate, created of permanent artificial constituencies that we know as states.
Perhaps not having a parliamentary system is the primary issue.
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