Silvermoon, like Dalaran, is probably drowning in magical artifacts with room to spare - somehow I doubt this would be an impossible draw on Silvermoon, just as it wasn't on Dalaran (which likewise had been destroyed in the Third War). It is also neither arrogant nor selfish to refuse to drain the life directly out of living beings.
They're not slaves to simply be "put to work," they were citizens of Quel'Thalas just like their Blood Elven peers. They also had no stated compunctions about carrying their weight.
"Maybe," "could have," "possibly," and the litany of other possibilities that were again never even tested. Handled properly the High Elven contingent could've been a boon to Silvermoon - just like they were during the Zandalari crisis in TBC, and especially with Sylvanas having forced Lor'themar's hand to join her in Northrend.
That's deeply overstating their plight as well as drawing up a number of completely subjective denouncements that betray a personal bias on your part. The High Elves never asked for additional resources or to "eat steak" as you colorfully put it - they just wanted Lor'themar to recognize their decision not to indulge in mana tapping. He refused due to his own worries about internal strife. They fact that arbitration of some kind was never even attempted goes to show that there were no terms as you imply above. We don't even know if the High Elven contingent would've asked for additional resources, because they never got the chance to even do so.
Natalie Seline was a champion of the Conclave and aided Azeroth against fighting the Legion - so if she's "corrupted," then corruption is a super low bar and nothing to actually worry about in the long term. You can take your narrative pick.
Originally Posted by In the Shadow of the Sun
Lor'themar stood and turned to leave. They had caught him off guard, and the walls around him no longer held the assurance of solidity. He saw Aurora stand and stare him down, her chin high and defiant. Neither she nor Renthar spoke another word, and it seemed as if the sheer force of their hatred pushed him from the room.
He had no reason to fight them. He could, perhaps, offer his palms in penance, but they would only spit upon them, and in truth he could not find it in his heart to fault them. If he had held any hope of atonement before—and perhaps he had—the Plaguelands' desolation had smothered it, as it did all that lived and dreamed. These bridges had burned long ago, his own hand setting them to flame. (
Source)
He seeks penance, and when the High Elves refuse to grant it he can't fault them for their actions, nor even find it in his heart to fault them for doing so. So yes, he admits he was wrong, and when trying to right that wrong as best he could he can't fault the High Elves for finding him contemptable.
And I said before, if Lor'themar had handled the Umbric situation differently there may not have even been Void Elves to begin with. We'll never know, now.
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No, at no point did I mention Golden, or Anduin - I'm talking about the High Elves, Blood Elves, Void Elves, and Lor'themar's errors in judgment. The only one who's made a bad faith comparison here is you, and I can only assume in an attempt to dishonestly detract from an argument you dislike. I even framed the loss of Umbric's people to the Alliance as a bad thing, further detracting from your spurious and incorrect argument.