Sargeras finished his corruption of Argus's world-soul, but the world-soul didn't wake up completely and remained in a deep sleep.
The so-called sleeping state referred to the fact that the world-soul could not transform into a titan and appear in front of others. However, Argus's consciousness could already have some limited soul communication with many creatures.
How should it be put? It was obvious that Sargeras had 'accelerated the maturity' of Argus's world-soul!
