I’m more optimistic on decoy wallets. Of cos they don’t address all types of attacks (no security feature ever does), but one can easily imagine how they can be useful *at least* in the case of non-targeted attacks, which will probably become more common when Bitcoin goes mainstream. It will not be unusual for a random person on the street to own Bitcoin.
The anecdote you cited about one victim refusing to give up anything and telling the attackers to shoot her: she might very well got lucky - she could’ve ended up dead.
At the end of the day, stories/anecdotes are just that. They don’t have predictive power. We don’t have substantial data on how many users have used decoy wallets, and how many have used it successfully or unsuccessfully.
TL;DR: Decoy wallets are just one tool in a large toolset. Writing them off based on a few data points seems a bit premature IMO.