I agree with you, in large measure, but after the 2012 polls that assured me that Romney was going to win, well, come to find out...almost all the polls were dead-on correct in forecasting an Obama win.
That’s addressed in those articles, They were able to use landlines to known demographics. In 2016 we have changed a lot tech-wise, cutting the cord etc, and a lot of their demographic no longer talks to them. They Missed badly since then.