I'm familiar with the usual potential outcomes framework, and some of the high level machinery of Pearl's version too, but this 'type causality' vs 'actual causality' mentioned in the intro seems like a very unnecessary complication that just confuses things.

They use "smoking causes lung cancer" as an example of type causality. A counterpart in actual causality would be "Dave's smoking caused him to get lung cancer." Then they go on to talk about how these are such different kinds of causality.

They're no more different than "Dave has $35 in his pocket" and "the average american has $21 in their wallet."

Seems totally unnecessary. Am I missing something?