I agree with you on that. However, I would have to ask you which source of knowledge you use and how you alone can answer such questions when someone around you asks you: Where do you get the strength to do the right thing in a very difficult moment? What are your sources of strength, what principles do you apply to attain this mastery? Where do you turn in times of despair and insecurity?
Whoever seeks help from you needs some kind of label and traditional source. No one will believe you that you have developed your inner strength and wisdom all by yourself. So the question is legitimate to ask about the influences so that a person seeking your help can rely on what you say offers him the way to draw strength and wisdom. He must bring it to the test himself and make sure that what you tell him can be explored by him. In some ways, therefore, we all need some form of guidance and recognition that there are norms out there that form a community.
As long as such a question is not asked and someone feels comfortable in your presence as a matter of course, you have consensus, it is unnecessary to tell someone his sources without being asked. But what if someone wishes this? What do you tell him what has helped you personally? From my point of view it is not enough, for example, to list the great philosophers. It does indeed need a methodology and a conclusive concept. The only thing I have found so far is Buddhism. I wonder why you don't mention it because much of what you say seems to come from these teachings.
RE: Morality - Subjective or Objective?