The iPhone 7(+) has better noise cancellation that the 5S, not the other way around. As noted in the original post, a 4th microphone was added to the 6S to assist with noise cancellation. There may have been improvements in the 7(+) over the 6S, but nobody has done the review to tell us, which is my point.
For some people being heard when there is background noise is not so important. For most, it is critically important for critically important calls which happen from time to time.
