As long as we are talking about the nuances of this issue, we should be clear. The officer has the legal right to REQUEST that you identify yourself. In fact, the officer has the legal right to request just about anything to satisfy him/herself that you are not engaged in any illegal activity. That is certainly part of their job and I don't grudge them asking. What is at issue is whether they have the right to detain for non-compliance with that request. We all need to know our rights and just because the officer has the right to ask doesn't mean we have the legal obligation to comply with that request.
As I stated above, in most cases I don't really think this is an issue I would argue. I would probably identify myself to the officer and perhaps even show some identification document or other if they asked politely. Polite treatment of a law abiding citizen merits a polite response. In ANY case where this interaction took place, though, I would inquire of the officer what his/her understanding is of the law on this and whether they are clear on the fact that I have the right to refuse if I choose to. For any officer that has a clear understanding of this and is not afraid to acknowledge it to a law abiding citizen, I will respond to this professionalism with courtesy and (usually) compliance.
I agree that they are most often just trying to do a difficult job well, and I agree that it is in our best interest to be friendly with law enforcement. It is a delicate balance to firmly resist the gradual erosion of a controvertial right, while at the same time being part of the solution and not part of the problem. Being firm about maintaining our rights is part of our responsibility as citizens, though. When we entirely cede the responsibility for protecting our rights to the authorities that are trying to erode them, we have already lost.
Just trying to help with the OP's stated goal of getting us to think about and discuss this.