Don't take this as an invitation to bring him back, please, but... did Blizzard just forget about Nathanos Blightcaller?
I don't understand why Blizzard made a big build up to him purposefully getting himself killed for the pre-patch of Shadowlands only to have him referenced once, barely even by name in the entire expansion. What purpose would you have in a story for doing that with a character?
I think this is more of recognizing a constant issue with the writing of this game. I feel like they keep having ideas for characters and never ever develop any of them. It like we get the first 10% of a story over and over again, then maybe the 5% of the middle of that arc, and if we're lucky a reference to it ending.
The game feels more like a repository of abandoned fan fics than an actual story.