The example in the article can be fixed very easily and doesn't require immutable data structures. If you're fetching something from a url and you don't want to fetch twice from the same url, make the dependency the url itself.
More generally, one should be destructuring object properties (since he later did that anyways) at the top of the function. It's no more typing, but isolates property usage to one spot. Then pass them into the dependency array.
Seems very convoluted to do that inside the useEffect, just to show how "it doesn't work".
Especially because often a re-run of the effect will be desirable when some of the props change, not always the whole bag..
