If you read the book, the author would frame that in the context of the diagnosis and guiding policy. The diagnosis says what is wrong, or what the opportunity is, in precise terms. That eliminates most actions by making them obviously irrelevant. The guiding policy further narrows scope and may explicitly include the things you’re not doing.

But I think the big takeaway is that strategy is neither goals nor actions, and thus not a list of what to do or what not to do. Rather, strategy is a precisely defined diagnosis of a problem and a specific response carefully designed to leverage your strengths / advantages against the problem. If you have that, then the answer to what you’re not doing is very clear: “anything else.”

I agree with your synopsis of Good Strategy Bad Strategy.