it's no brainer.
Ranged classes are ranged for a reason. For e.g. in real life situation, gunners, artillery are all situated at high ground giving them line of sight advantage as well as the difficulties for enemies reach them. Is there any idiot who places their long ranged weaponry right in front of their enemies? That's like telling them to "im right here, please kill me"
In EE case, common ranged dps are hunter, engineer, mage, illu etc. Which are paper by nature (except engineer who goes into ironman mode, but once ironman mode they are practically melee already). Obviously they have to make use of terrain for survivability right >.>(who expects mage who uses cloth armor and low hp, eva, def to actually tank mob ._.)
On another hand, melee classes are warrior,knight, thief, MA, bd. Warrior/knight uses heavy armor, enuff said. Though eva in EE isnt that imba but at least those are some form of survival technique. Thus, justifying as melee classes.
So IMO, terrain exploit is really... not a fault of the player. The game mechanics itself forces player themselves to ulitise methods for survival.
Next thing to bring up are, bard soloing venin, kiting strong mobs. Arent all these a form of exploit as well? All these involved some ways of killing mobs without getting hit through running , terrain etc.
So literally, calling terrain exploit as an offense is... stupid -.-
Im a 50/50 knight so im not some random ranged classes who's promoting terrain expliots but rather giving a more objective view.