Such is the case with so much in Wow and Warcraft, many things not explained, we have to either use our imagination and the things already in the lore to try and guess how they work until blizzard actually explicitly shows us.
And they may never, sometimes it is such a small thing it isn't even on the radar, sometimes to them it is so obvious by putting two and two together they may feel it isn't necessary to explain, but what seems obvious to me might not be to someone else, and if I give an explanation, even drawing from the lore, without direct confirmation, can't really say for sure and it can be argued over.
Sometimes they like this, who's to say the cloth cuts only one way? Other times it gives players room to grow their fantasy, which can be a lot of fun for them. And a plus in this genre, and if excellent fanatic, that is really cool and fits into the lore comes out of it, they have been known to incorporate it. Sometimes though something isn't directly said, it's pretty obvious there is only one way it can be taken if you consider the lore.
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Probably because i like that part of their fantasy too. The dark elf caster in world of warcraft is very different from its counterparts in other games, i like the noble good night elf arcane users, something theyy aall were before addiction compromised that.
I also like how integrated the arcane is in the night elves throughout the Long vigil, and love the details of the fantasy too, elves filled with arcane power with glowing eyes, a well of arcane power that nourishes nature, (in other fantasies, your dark elf caster arcane power was the antithesis, of nature, in wow, it was different, they complimented nature, and wow's dark elves also loved nature too, it was a core part of them in the arccane era even though practice became marginilised, and vice versa the arcane was still a core during the vigil era even though it wasnt used for spellwork - different and rich) even their restriction on then use of their arcane power for spells i always viewed as a temporary thing and one of the great things to look forward to about the night elves was when they would start embracing it again.
You have to have things to look forward to in a race, it brings exciteplant and boosts your immersion and attachment to your character and the world. WC3 ended with legion returning and the need for a ban no longer necessary. Since these guys were portrayed as being the most naturally gifted and attuned to it, with the ban lifted I expected they would rise up in the arcane once more and build their beautiful cities.
In truth I was very excited to see advanced night elf architecture, to see the pre-sundering wonders. I like seeing wonders, So I loved the moving tree houses, the cholera dragons, the star calling Priestesses, the elves that could change into animals, I loved that, and it only what my appetite for more, having seen the nature wonders, I wanted to see the fabled arcane ones they spoke of about the pre sundering empires.
I loved their uniqueness, these guys had a full on nature aspect to them, but it had the arcane fully part of it , included and visible, not vague like other fantasies, this was unique, druids that called on the stars and moon, an arcane well.
I also lived that they tried to make them a purer elf, reflecting that these were the original elves as @
Mace explains above. All elven traits, outside humanities reach or capability were amplified in the night elves, from character, perfectionism, magical aptitude and display...whether arcane power in a wonder pre sundering empire or nature power through world trees, walking and talking trees and animals, covering a continent in mist etc. Blizzard did not shy away from letting loose on their imagination, I especially after seeing those ruins, I couldn't wait to see what they would do when the night elves started building again with the arcane pre-sundering cities. Silvermoin did not disappoint when they did it, it gave me such hope. Didn't realise I would wait Over 10 years to see Suramar, but it did not disappoint either.
To be honest I really like all the different facets of warcraft elves love the most recent addition, void elves, can't wait to see what they do with them. Why do you think I get so passionate about them and so annoyed when they don't write them playing out well or according to how they designed them.
It's because when they do it well it is so nice, you really want them to do everything concerning them with the same level of excellence they are supposed to be as in game too, so when that doesn't come of well it is annoying.
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That is like saying in 8 years time after blizzard has shown the u understanding of void and light much greater in humans, and intolerable humans even now u understand you can wield the void without being evil and accept the void elves, that they are still marginalised because of the cathedral response.
Their initial welcome was tough, same as the DKs or DHs, but this was in the pre-cata patch, dude. Wolfheart showed Maiev was whipping up highborne hate and only a handful of night elves followed her. It showed Malfurion AND Tyrande wanted those highborne back in the fold appreciating night elf society has evolved since the Long vigil. I mean why do you expect them to forever hate every highborne caster even those who are responsible and UNCORRUPTED? It's gotta change sometime, and as greater clarity cones of the highborne and the different groups of them, especially as cata quests show you night elves keen to embrace the arcane and only Maiev hating it...why would you continue to think the treatment in the pre-cata scene still stands and the situation hasn't long since progressed from they.
Surely by now you should see the problem was not with the highborne for being highborne - no, that is irrational, and elves are not like that, humans can be, but elves on the whole are not unless they go crazy (cough Maiev), nor is the problem with the arcane itself as you know even in the nature filled long vigil they are infused and surrounded by the Wel of Eternity and export it's waters all over the place as moonwalk. The problem was always with reckless and abusive use of magic, and anger was against the highborne caste that abused the magic and brought the Legion.
What happens when they meet a bunch of highborne who are corrupted and do not abuse their magic? Even if they hated the casrpte for its role, do you think it will last forever? No. And this is precisely what Wolfheart and Cata actually showed.
Most night elves don't hate their highborne or marginkise them, a lot of night elves opted to study the arcane again, do not forget it is in their make up, they are drawn to it by nature, this should not surprise you. Their druids and priestly sides will ensure those who go that arcane wield it with the respect it deserves and do not abuse it in the way that destroyed them, but they will wield it and it is a key and growing part of them.
I don't know how much it's grown, but it was growing, the Moonguard, nightborne and Farondis appearances in Legion should further increase that share