I have to say I think thats revisionist history. From the year Howard came in on loan, until 2014 we were such a better defensive side, our best stretch in the PL by far. It was only his last two years we started shipping goals again. 2011-2014 was 40, 40, and 39. We had a champions league defensive record for those years.
His save percentage in those years was all where Pickfords is now, it was just his first 2-3 years were so good that the expectations were sky high. Id suggest he was elite for a couple of years, and then "merely" good after that, until poor at the end.