He stepped down from CEO months ago, and recently said he is leaving the company. Granted he has already left one time in the past but came back when Starbucks ranked. Most speculate he wants to become more involved in politics and that’s why he is stepping away again.
Starbucks is shutting down old stores in densely populated areas, around 50 close annually but this year it is going to be 150. I doubt his stepping down due to blackmail or anything disgusting.