This is the page I was referring to previously. It has a name in Japanese, so I understand we create a proper page for it. But in essence a false ko threat is just a reading mistake. Sure, the reading mistake has an impact on the ko, but it has essentially nothing to do with the ko.

So on one hand, if this page exists, dead ko has a reason to exist as well. But on the other, I wouldn't put such pages in the gallery. They are useful to refer to, during a ko discussion, be it of particularly bad players: is a false ko threat, but it doesn't matter because they're fighting a dead ko anyway.