That was almost undoubtably why.
Mike has a super nice house now with tons of space and a beautiful pool. I lived in Seattle for over a decade, and for him to get anything even remotely close to what he has now would cost an absolute fortune. Anything comparable within the Seattle city limits is going to see you pay 4+ mil and still have no pool, no backyard, and your exterior wall is going to be an arm's length from the house next door.
I'd be willing to bet large sums of money that he was just visiting that famous house while he was there, and not that he's moving to Queen Anne.