Ever acquire a title you didn't ask for? Sometimes a nickname or identity gets chosen for us by others, and it may not be what we would choose for ourselves!
It's also a sad situation where a person sees themselves "one way" but everybody else views them differently. For example, the person who thinks themselves a comedian often becomes the joke.
The idea of a guru or "guy-who-knows-it-all-and-everybody-listens-to" may be a coveted identity by some... but most of the people I know who "have their stuff together" rarely have the pride or hubris to consider themselves a guru!
In reality, the best nicknames are the ones given to us by others. You may not like it, at first. But with the humility to accept that perceived reality, you can choose your actions to change an undesired nickname to something aligned with the real you!