For real projects, but for someone just getting started I think it makes a lot of sense to start with core language fundamentals (I notice that, at least from the table of contents, there was no mention of build systems or frameworks either). Lots of newly-minted JS devs today know relatively little about what it means to use plain JS, which means they don't have as much perspective on what their TypeScript and JSX actually turn into, which has a meaningful effect on informing decisions.