It is a money decision.  Trump money-balled the electoral college and targeted just enough to win.  It is a poor investment to invest in races that are so overwhelmingly blue.  The result in the current scenario us that the most populous centers do not get a seat at the table and have little leverage to gain any. Thus the critical loss of the state tax deduction that hurts them disproportionately.  (now they have to argue that their wealthy taxpayers deserve a break.)