I would agree except for this little known bit…
Dark Naaru
https://wowpedia.fandom.com/wiki/Naaru
Also, it is my bet that the Hallowfall Crystal we see is a Naaru of some kind. And you can see it shifting into a void state just like what is described as what a Dark Naaru or Void God is.
Only major difference is that it is shifting back and forth at a rapid pace compared to anything we have dealt with prior.
So I am betting something is a foot and is forcing this state of change and perhaps farming/gathering the energies of either or both states.