Hmm..
Y’know, rather than the Dark One lying about caring about equality as some have suggested it might be better if that was part of they mythology that came around as the story of him as a mortal got exaggerated.
(That would help avoid the whole common issue of making “person starting equality movement was evil all along”)
Like say originally he was just an ambitious warlord, someone who would fit in with all the jerks on the Western Continent.
It would thus be only post-death that the tale of their greatest leader of the goblins was assigned a champion of the oppressed.
While I think Rich has hinted in forum comments the tale of how the Dark One came to be is not completely accurate, it would feel dumb and cliche if he has a mustache twirling moment about he lied about wanting peace.
Also there might be some existential drama to be mined that as a god one has in some ways less control of their destiny as a mortal, as Loki angrily points out.
The good news is that means The Dark One is possibly capable of mellowing out over time...