I don’t view Jesus as repudiating the term. Instead, I view Jesus as seeking validation of the believer and helping him grow his spirituality and theology.
Once one knows only God is good, then one should ensure everything s/he calls good is God.
I also find the reasoning to be similar as to why Jesus asks "who do you say I am,"rather than saying, “I am God.” It is granting necessary freedom to the believer, while growing the believer to greater spirituality.
Turn the question around: Why would the rich man address Jesus with a term which was reserved for God alone?
Consider also Luke 8:38-39
The man from whom the demons had gone begged that he might be with him; but he sent him away, saying, 39 “Return to your home, and declare how much God has done for you.” And he went away, proclaiming throughout the whole city how much Jesus had done for him.
Jesus didn’t come to be exalted. He came to humble Himself as a servant to man and mankind. So He really wasn’t looking for anybody to praise and exalt Him on earth. He would become glorified in heaven, when He returns to His Father. He reminds the man in this way, that we are to seek God, the source of all good.