My duplicate question was just closed for being an exact duplicate.
So naturally I looked to see what this answer is.
This answer doesn't really apply. It's a "me too", but it doesn't tell me if this won't happen by policy, will happen maybe, or anything.
Note that I'm not complaining about the answer, it's relevant on meta, I know. I'm complaining about the "this question has been answered here:" when it hasn't been.
On a main site, this banner would be incredibly frustrating and lead to "THIS DIDN'T WORK" or various other comments on the referenced question asking for answers.
In a similar vein as "Marked as duplicate text doesn't make sense for questions that have no answer", this banner is exceedingly unhelpful, and should probably be changed to something like "This question has already been asked here:".
Simple, true, effective.