Yes, to reduce expectations but also as a world class athlete racing a pack of world class athletes, he cannot dictate pace. If the pack doesn't want to run WR pace there is nothing Kipchoge can do about it. He cannot by himself in a competitive race go out and run WR pace from the gun. Doing so would be foolish. He could blow up and get caught by the pack. Don't forget these are professionals racing for money which gets paid out by the PLACE. He is racing the other guys. Time is secondary.
Sorry, you couldn't be more wrong. Time is his primary objective. That's why he says it's his main goal. That's why there are pacers to lead him at WR pace. The WR bonuses, the future appearance fees, his legacy as an athlete all get a boost if he runs the world record.
Kipchoge's time is the only thing anyone is talking about regarding Berlin.