The practice of Void being forbidden is not disobeying an order.
All I read there is they were studying a scientific branch the practice of which is forbidden (just like in real life, scientists can research and experiment with bombs despite them being forbidden to the general public).
I don’t see any orders either, just Rommath being… Rommath. sigh Whining as usual.
They were told by the government to cease and desist and refused. That is absolutely grounds for exile given the history of Silvermoon and it’s government.
When did this happen?
Especially after the Scourge, Quel’thalas became more authoritarian in nature. Practicing something forbidden in that instance would be a form of ignoring an order.
Likely forbidden by law. Also, I get the real life science angle, but fantasy tends to have their governmental structure a little bit more feudal than real life scientific pursuits.
Also, seeing as it’s related to the topic of the Void, I’ll post the description of the Void and the Void Lords from Chronicle 1, just for posterity on why the practice is likely forbidden.
From the moment the cosmos came to be, dark spirits within the Void sought to twist reality into a realm of eternal torment. These entities were known as the void lords, and they had long watched the Pantheon and their journey from world to world.
From the moment the cosmos came to be, these Void Lords were lurking in there. Sounds like unsafe energy to me.
EDIT: Also:
I would describe Rommath as belligerent more than whiny.
We don’t know exactly when.
I mean, how do you know this happened?
Because dialog and quest text tells us so.
No, they don’t.
Dialogue and quest texts say they were exiled because they studied the Void, the practice of which is forbidden.
Nothing there says they refused to follow orders.
Do you really think they didn’t tell them to stop, and just kicked them out without warning?
Man apples to oranges. One thing kinda doesn´t relate to the other… Orcs falling prey to “muh ancestors whispers” is well documented and supported by historical record in TWO universes. No surprises there.
Fact is, Visions of N´zoth and A Thousand Years of War both imply Alleria WILL fall prey to the void whispers at some point in the future (it´s a “when” not an “if” sourced by two different media). So let´s not pretend Umbric is a poor wittle victim of big bad Rommath, cause guess what: not even the canon Umbric believes so.
Rommath walks up with a something-eating grin and an eviction notice. Something tells me it didn’t happen quite that way, but you get the idea. 
Considering the dictatorial habits of Quel’Thalas and that High Elves were exiled without warning, yes. I call it “the Blood Elf way”.
EDIT: Exiled or mind controlled, like those poor elves in Silvermoon voicing their opinion against allying with the Horde.
Likely in a different situation, as during that time Quel’thalas was still loyal to Kael’thas, with Lor’themar merely leading in his absence.
Also, didn’t Rommath exile Umbric and his followers? Lor’themar exiled the High Elves back then, not Rommath.
Nah, it was more like:
Lor’themar: Drink!
High Elves: Aw hell no!
Lor’themar: Then bye Felicia!
There’s black hair in a teaser? Am I blind or missing something? :o
I just want white-blonde, silver-white hair soooo baddddd I don’t need any blonde or brown or red colors as long as we get black and super pale white-blonde :(.
Also I really love this mockup you made! Looks so nice!
Exactly. I know a few real life leaders who would be proud of this kind of decisions.
I mean, yeah but we aren’t playing the Mogu, now are we?
The Blood Elf leadership has been shown to actually care about their people. We even see Lor’themar’s personal demons regarding this issue in multiple different pieces of literature.
What if they went with the idea Taliesin had a while back about class skins changing the names/look of spell classes to better fit with the lore of a specific race or frankly just as a new thing to collect. Think Shadow Priest with a holy light skin. All the same abilities but now it looks like holy magic instead. I think stuff like that would be an amazing addition to the game and could make for even better customization without adding new classes.
Here’s a link to said video: https://www.youtube.com/watch?v=rTcoK4OXKTw