For the others in the series I've no idea. They've been on my reading list forever.
Would you want to be related to Trump if the economy tanked and social services started breaking down?
If I am the last person on earth, i effectively "own" the entire earth, but it means nothing.
Same for a man staving to death on top of a mountain of gold.
Which makes this billionaire New Zealand apocalypse compound trend all the more ridiculous, if society collapses, being a billionaire is going to mean absolutely nothing, you would think the money would be better spent ensuring that doesn't happen in the first place
The ancient patrician families had trouble with going extinct. Their decline started long before the imperial period.
Later European kings had the same problem, sometimes just failing to produce any heir. It only takes a single generation and the family is gone.
If anything, I'd attribute family extinctions like this to monogamy. The two standard defenses against a failure of this type are (1) letting a man marry into the family by wedding a family daughter (as opposed to having the daughter marry out into the man's family); and (2) taking more than one wife, which offers dramatically greater opportunity to reproduce.
I wanted to make that point when I read this line:
>> But the Avars ruled Central Europe for over two centuries, and it is not a given that their civilization had no worth and did not represent a future we would have flourished in.
A civilizations worth is always measured by those who might seek to control it. You could have a bunch of people getting on just fine, living out perfectly normal lives. But if there isn't any way for them to produce excess - be that labor output or extraction of natural resources - then they are not seen as valuable and will not be written about.