I entered the discussion late, but as far as I know, it's about whether Argus is as powerful as some thought. The discussion started with someone saying that we just defeated a being that could destroy the universe in a single hit, we should be able to fight Sargeras (who is nowhere near that level in lore as far as we know) just fine. Keep in mind that Argus was both newborn and in an avatar instead of a full fledged Titan (as said by Ion, "Aggramar, for example, is not the actual Titan Aggramar. The actual Aggramar would have stepped on you like an ant. <..> And it's the similar stories with some of the others Titans that you may deal with"). If he could destroy the Universe in a single spell, the Titans before, and Sargeras up until now, should be able to do the same thing - which obviously wasn't the case. Logic-wise, EoAT being a universe-burster spell doesn't make sense, as it'd kill Sargeras in that case. Would Sargeras keep Argus around unattended if Argus is way more deadly than him and could kill him with little preparation? Why would Sargeras just leave Argus alone - and even empowered him - casting EoAT if it's going to destroy the Universe, which means Azeroth would be gone as well? That sounds as right as claiming that N'Zoth empowered Deathwing to literally destroy Azeroth (which would go against what the force of the Void wanted).
It'd make more sense if EoAT is more in line with literally every other abilities in WoW (and I'm talking about lore-wise instead of just game-mechanic): it can either be resisted / countered (for example, it can take the life everything, but beings more powerful than Argus - i.e: Sargeras - could defend against it just fine) and / or have a more limited range. The argument that EoAT can destroy the universe in a single hit (which would make it, and Argus in turn, the most deadly force in WoW story by far) is only really backed by its own tooltip - which as pointed out, may not always be reliable (we've seen other "kill everything" spells that no way can do what their tooltips said - i.e: Yogg's Extinguish All Life). It could simply be just flowery language (and yes, the "one hit" part is important).
Assuming that EoAT indeed destroy the Universe in one hit - obviously, Blizzard don't need to go as far as rebooting the servers. I wouldn't even demand them to create a new skybox to reflect the 3s of WoW reality between the spell hit and end of the encounter. That wouldn't make much sense in term of cost efficiency.
However, they could easily show the Pantheon drop dead after Argus finished casting if they want to. They could have destroyed the Seat of Pantheon if they wanted. They could even go the Deathwing's Cataclysm's way of having the screen fade to black. All of those mechanics have been implemented in other encounters before. None of that happened - so one have to wonder, if it wasn't show with in-game mechanic, didn't explicitly stated in lore, and doesn't make sense lore-wise - would it really work the same way as people hyped it to be? Saying that "those were in-game depictions, the lack of them doesn't say anything" doesn't hold, as EoAT destroying the Universe in one spell is game-mechanic (its tooltip in particular) as well. No where in lore said the same thing, just - at best - that Argus has the power to usher in the end of all things and unmake the universe. It didn't say he could do that with a single spell which is the point of the current discussion, if I'm not wrong. All in all, with what we know so far, maybe EoAT can destroy the Universe with a single hit, maybe it can't - but the later is more likely to be the case.