Are you talking about this lay person
en.wikipedia.org/wiki/John_T._Noonan,_Jr.
non-theologian, non-authority on the Church? (Even though he, as the wikipedia article suggests, is an ethicist, was raised Catholic, etc.) In my reading on Noonan, he does not speak of the term “moral relativism.” That is your phrase, which you keep on attributing to the Church without authority on your part to do so, and which you keep, along with this false premise, asserting that our Holy Father “denies,” as if PBXVI is being deliberately disingenous. (Lying) As here:
Again, this is offensive. You are making a false statement and accusing the Pope of prevaricating on your false premise and what you assume are the true (not) premises of certain lay figures who are not part of the Magisterium and not authorities on how doctrine develops (as opposed to “changing”) in the Church.
Development of a doctrine is a different dynamic and is not even in the same galaxy as “moral relativism.” That is the false equation, one you keep on making, and then asserting that our Pope is “denying.”
Moral relativism refers to shifting standards which change according to circumstances, especially of the actor. Moral relativism is the opposite (obviously) of absolute moral standards, which, as a system, asserts certain principles which are fixed.
One thing that non-experts in moral thelogy (of which, I’m sorry, both you and Mr. Noonan are) often do not understand is that it is the principles which are fixed. Variables are indeed taken into account in moral theology, but without understanding the process for placing those variables in the correct hierarchy within the absolute structure of moral decision-making, it is possible to get derailed. (Or to assume “relativism.”) This is why fully trained Catholic apologists with credentials spend years in Rome, learning these principles and their application, and are able to speak lucidly and authoritatively, having understood these dynamics and their structure within a theological and philosophical framework.