Actually, their situation is different from the other races, because the society is not unfamiliar with druidism or CEnarius, and by the time the Nightborne are done, it is well established that there has been the Cenarius connection in their past (his home is literally the forest next door). Whiles they ahve gone a long long time without this, it is already in the Night elf lore they are tied to, and thus there. Furthermore, they get introduced with interactions and help from druids, and we see thy developed some expertise in nature magic wielding which is likely from the vein of pre-druidsm before Malfurion took the art to the heights it reached.
I would suspect the earlier versions of druidism, while useful didn't have much use to the advancing civilization and paled in comparsion to what the arcane could do, which is why most night elves gravitated towards the arcane, and only take alook into druidism again when they are forced to by the events of the aftermath of the Sundering.
Fortuntaely for them, they did, cos it proved quite essential and also the solutionto curing addiction. The Nightborne while not having the druid class, seem to have a lot of presnece of it in their story, their history and they're shown to be wielding nature magics - that's a lot for a race that can't even be druids.. yet.
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Gilneans, who become worgen because of a course, they aren't naturally worgen at this point.
They are basically a group that had nothing to do with druidism, and were given it to make worgen palyable. Nothing wrong with that, just pointing out that they had nothing to do with it before that event. Prior to cataclysm, Worgen was still pretty much a story we were following a night elf priestess from Ashenvale forest to investigate what shenanigans were happening and retrieve a dangerous artefact. The worgen we followed were not shapeshifters either. They had nothing to do with Gilneas.
I know, that's why I specifically mentioned the worgen playable class, which is what we are talking about. The original worgen, which is not playable, has a history connected with the Night elves because they're night elves we find out much later.