To delve more into the matter, if my assumption and recollection is correct (which it probably isn't)... since you can't do such things as burn or freeze or shock or anything like that without aspecting your aether, you're just left with what aether is at its base - life energy.
So, manipulating that means diseases, pathogens, and decay. And if that's the format you're sticking to, then it's not too far-fetched to believe that the Arcanists would hone and improve on those techniques. So whether the specialization is intentional... or that it's a restriction that they simply chose to embrace... is hard to say.
Then again, as I mentioned, I could just be horribly misremembering.
So, manipulating that means diseases, pathogens, and decay. And if that's the format you're sticking to, then it's not too far-fetched to believe that the Arcanists would hone and improve on those techniques. So whether the specialization is intentional... or that it's a restriction that they simply chose to embrace... is hard to say.
Then again, as I mentioned, I could just be horribly misremembering.
~