The range of interacting with objects is shorter than intended & shorter than the mouseover interact icon indicates. This has been a problem since Cataclysm classic, although it hasn’t really been an issue other than a minor nuisance since it was usually just a quest item and you’d right click on it while it shows it’s interactable, it’d say “Out of range”, you’d take a step closer and be good to go.
However there can be situations where you cannot get close enough to actually interact. One such instance is in Mogushan Palace after killing Gekkan, I was not able to interact with the treasure pile and would constantly receive the error “out of range”.
The interact range should be the same as what the UI says is the interactable range.