Do they not get their powers back?
Maybe the real power is the friends we made along the way?
But… no actually. There was this whole thing with reactivating the “Mother Oathstone” that should have given the Aspects their powers back but that plot point hasn’t moved forward since the Incarnates escaped.
Dragonflight is not over yet so maybe there is still some time to go over that little detail.
In 10.2 Tyr will finally be rebuilt, so probably the answer lies in that or in the raid ending.
There is some hints they will accept a blessing from Amirdrassil and regain power that way.
Vyranoth would not be cool with them going to papa Tyr and Aspecting it up again, and they seem to intend her to be the representative of the minor flights.
They get blessed by the nelf tree and have to defend the nelf tree or risk losing their aspectral power.
So the Horde FINALLY got a positive dragon (and an aspect to boot) just for said dragon to doff his tauren name and swear to serve nelves in perpetuity.
Did they ever explain what Oathstones were, or is this a Covenant Sigil deal?
They did, but only in the book.
Oh, of course they did.