This is most confounding in the context of when Joe Biden actually faced his steepest competition: the primaries. It was all but decided that Joe Biden would be the nominee before we knew the sort of tragedy that he'd be uniquely qualified to address.
That's a blessing worth registering. If we're intent on not attributing this to dumb luck (which it may be), it's heartening to think that 46's best attributes were appreciated before we knew how they'd be needed.