The sign on the left directly addresses the map, making an *unsubstantiated claim* that its mere existence is criminal. That could be considered libel. Ever notice that newspapers have to refer to actions as "alleged"?
Next time you hike somewhere that's on an easement instead of publically-owned land, make sure you don't take any pictures, post a trip report, or even mention you were there, because that's the direction that many people's opinions on this thread have taken. You can have access but only if you don't tell anyone about it, because if the access ever changes, you have to forget you were ever there.
Note that I am *only* addressing the issue of the sign and the map and this particular landowner. The issues of property damage and/or any issues with another private landowner who grants access but not an easement are a separate matter altogether. And for those issues, the landowners chose to simply attack TB's (admittedly questionable) actions, instead of taking more appropriate actions that they would have had to anyway if the map had never been made.
Personally, as a landowner I would have used the map, worked with TB to mark or unmark features on it, label acceptable access points, and then I would have posted the land for no bushwhacking, access on marked trails only.