By this definition we have 2 caster tanks already then. So if redundancy is a valid argument against something like Samurai via their weapon choice, then this would also apply to future mage tanks being redundant when we have Paladin and Dark Knight, who both cast magic spells in an instant cast fashion.
In my opinion, Casters are casters because they have cast bars, whether it's a channel or fill guage. Yes instant cast spells are still "cast" but now it's just arguing semantics.
I certainly wasn't arguing for any kind of a ranged tank because that's an even more absurd idea than a tank that primarily has cast bars for their attacks.In terms of the idea of distance, that much is fairly irrelevant. Think about times you solo, need to move in close (e.g. WHM Holy), or even use as a means to increase DPS (like SMN were technically moved to do during the 2.0 era, since books as weapons added a noticeable increase). You're in melee proximity for those cases. What you might be thinking of is a ranged tank, in this case. Those are of magic use or physical, as was the case of 2.0 BRDs kiting FATE bosses around, since the point is to simply play in a way that keeps distance between you and the target(s). Outside of kiting or fighting ranged-only mobs, they don't really exist for obvious OP status reasons lol.
That's one definition sure, but it can also be applied as a gameplay mechanic and not an identity, that's how words work they can have multiple definitions. And in the viewpoint of games development particularly for MMO's, a Caster is someone who casts spells usually via cast bars. You don't call Death Knights in WoW casters even though they cast plenty of spells, but you'd call Mages casters, Warlocks casters, etc. etc. You're really just arguing semantics here.Again, the term caster is simply a title or identity, it's not a reflection of mandatory play. Instant cast spells, spells with cast time, spells that are channeled, etc. are all part of the identity of "caster". That is, a character that utilizes magic as their primary. Technically, if PLD in this game could cure groups reliably, they'd be considered a caster too if they choose to focus on healing lol. Since they're more melee oriented though, they're simply a melee or tank that can cast spells. Even the term "melee" is simply a description to identify the primary means of doing their job. Casters can melee too, but you rightfully wouldn't label them as such.