On the other hand, AlphaZero seems to play to obtain a specific, although gradually accumulated, positional advantage that ultimately results in a resounding victory. It is happy to sacrifice “generally useful” material to get this.
AlphaZero plays chess in a manner that is completely unlike how humans, or even human-designed chess programs play chess. A human grandmaster does play much like you describe yourself playing: accumulating piece advantages, and only making limited sacrifices to gain position, when it's clear that the positional advantage outweighs the piece disadvantage.
AlphaZero, on the other hand, plays much more positionally. In its games against Stockfish, it would make sacrifices that Stockfish thought were crazy, as Stockfish was evaluating the board based on pieces and AlphaZero was evaluating the board based on position.
Epistemic Status: Everyone already knows about it?
I've been thinking a bit about two different manners of pursuing a goal.
I haven't come up with a catchy jargon for them, and I don't know of any existing catchy jargon for them either. General v. specific planning is pretty bad, but at least for the purpose of this post I'll stick to it.
I know they've been discussed here in one form or other, probably many times, but I don't think they've really been explicitly contrasted. I thought doing that might be useful.
Here are some suggestive, if imperfect, contrasts, illustrating what I mean.
Examples
Sketches of Definitions
If we want to stop giving examples and start talking about featherless bipeds, there are a few different ways to describe the examples above.
Misc Notes