It sounds like the point of this story is to illustrate by analogy that starting from first principles is sometimes a silly way to approach a problem, and by extrapolation that it's a silly way to make an AI that plays Go well.
Making an AI that plays Go well is not (and has never been) the real goal. They're trying to learn how to build a AI that can solve any problem.
I don't think that's the point of the story. In the story, Sussman says that because the initial state of his net was randomized, it will "have no preconceptions". But that's not true. It still has "preconceptions", but randomly chosen ones. Because Sussman didn't know what they were, that didn't mean they didn't exist, any more than closing your eyes means the room is empty.
The Taoist concept of the uncarved block, referenced in the title of the koan, refers to naturalness and simplicity. I'm sure someone more expert than me can give a better explanation but it seems highly relevant to the idea of learning to play Go based only on the rules, rather than any human tradition of strategy.
Making an AI that plays Go well is not (and has never been) the real goal. They're trying to learn how to build a AI that can solve any problem.