Honestly I hope we don’t see Arthas in any large story capacity because if we do guaranteed they’ll try to redeem him and make it seem like he wasn’t in control of his actions, much like they’re doing with Sylvanas. But in the case of Arthas it would be… much worse.
Much, much worse.
Pretty sure it is just invented headcanon that managed to weasel into wider acceptance. Only thing that would make me think Varian isn’t going to make a limited appearance is Metzen unavailable (he is clearly voicing Thrall, so not that), avoiding the muscly macho bros that dominate the franchise (Draka, but no Durotan, no Grom, no Brox, no Blackhand, no Lothar, etc.), or wanting to let Anduin overcome his situation without dad helping.
Problem, I think that’s what their going for.
Remember the very ending of the Icecrown raid?
Arthas looked at his father saying “FATHER, IS IT OVER?!”
Unpopular opinion: Good.
I don’t trust NuBlizzard to “bring back” Arthas in an appropriate way. I also think Varian’s story is over, and bringing him back strikes me as blatant pandering.
I don’t think you know what the word “probably” means
It was just speculation based on what we know about the Legions soul engines. I never said it was what actually happened.
Then again, I am talking to someone who hates everything in the game that isn’t macho human elitism.
I suspect it’s probably one of those guy trope things. Bomswamdi strikes me as the kind of guy you might want to visit once in a blue moon but would make a horrible next door neighbor.
We also now know EXACTLY why Arthas saw “Only Darkness before me.”
That hand of valor is still unknown but the current theory is that it’s either Rezan, based on him declaring Vol’jin the future of their people, or the Arbiter, recognizing it was not his proper time and sending him back.
Maybe eventually Vol’jin will want his dumb urn back too.
That is the general theory, given he proudly claims that he is a ladies man.
But it is just at theory… A GAME THEORY!!!
Sorry but I just had to.
I wouldn’t put too much stake into this. According to Sylvanas, Saronite also completely destroys the soul but she still had a spirit that could be sent to the Maw after she jumped off ICC. The real reason Varian isn’t showing up is because they don’t feel like using him, if they do they’ll just say that’s not how Fel works. They’ve retconned so many things for Shadowlands I’m surprised people think they wouldn’t change this if they wanted Varian back.
We haven’t seen Varian back for the same reason we haven’t seen Grom, Tirion, Doomhammer, Durotan, Lothar, Terenas or the legion of other heroes that have died in the Shadowlands: the writing team just doesn’t want to use them.
That said bringing either of these Arthas or Varian back would be dumb pandering when their stories are over.
According to my man Lucifer, there’s a special circle reserved for people who say “I just had to.” 
Arthas was part of Uther’s story. So unless that isn’t over, the best we will see is a cameo of him being freed from the Maw…