Yes, I think that's completely wrong. It focuses on the advocate as some kind of special role, but I think the core problem is preparing for a court case, and I don't think it makes sense to focus on him.
I think an accused should be able to make strategy notes for a court case and be able to have those be secret from the prosecution, and to look up things for these purposes, and, to use Google docs etc. if he so wants.
I also see that some other comments describe that work product has previously been treated as a broader notion with less focus on the advocate and more on preparing for the court case, so I'm far from convinced this has been decided correctly.
I understand why you feel that way, but the current policy is not in the direction you are hoping for. The important thing to understand is that all evidence is available by default, that privilege covers the exceptions to that availability. Privilege is construed narrowly, and for now, communications with your advocate, or notes prepared at the request of your advocate, are the sorts of things that are covered. Your own private notes, or chats with your friends about the state of your case, are examples of things that are not covered.
Work product was treated more broadly in one case by a lower magistrate court, but the court making the decision in this case is not bound by that lower court's ruling. What will be interesting is if this ruling gets appealed up to the sups. I doubt the decision will be overruled in any case.