I think this is another example of people expecting athletes to be commendable people with character and integrity. Many are, however, many aren't.
In sports, many of the people are just there for physical attributes. They shouldn't be considered experts on ethics, statistics, impartiality, judgment, politics, morals, etc.
So when someone asks an athlete a question on if they are the best, why do they expect not to get a dumb ass answer??