I'd trust the brilliant mind behind Bitcoin to hold onto some backups of keys worth half a billion dollars. Since you never know, such a a thing could come in handy someday.

I wouldn't, you can be a genuis and still be lazy about backing up and rotating your super private personal key.

Alternativly, he could be altruistic and deleted the Statoshi key to protect against manipulation, including from his future self.

There were many years where the keys guarded bitcoins worth approximately zero.

And shit happens, even to geniuses sometimes.