As perhaps the last person to play him, I think he withdrew from the scene due to his perceived views of how the game of CM was not being played within the purity of his worldviews (realism, no flags, abhorrence of gamey force picks, etc) and likely from burnout.
That is just my opinion from my short time playing him and reading his posts. It should not be construed as putting words in his mouth, nor inferred as badmouthing him: simply as best an answer to your question as possible.
Cheers!
Leto