Conversation so far:
What did James Levine do with the Opera?
During Levine's tenure, the Metropolitan Opera orchestra expanded its activities into the realms of recording, and separate concert series for the orchestra.
Was he a singer or writer?
he was named principal conductor of the Metropolitan Opera in February 1972.
How long did he work with them?
Following a May 2011 performance of Die Walkure, Levine formally withdrew from all conducting engagements at the Met.

Question: Why did he withdraw?
Self-contained rewrite: Why did James Levine withdraw from Metropolitan Opera?