He still has the same pic as his profile pic (the pic was a result of our inside joke), why?

What does this mean? my ex has the same profile pic on instagram 1,5 years after of us stopping talking?

He put that profile picture as a result of our inside joke (I was teasing him about his hat and as a result he changed his profile pic to him wearing that hat). He still has that picture as profile pic

He still has the same pic as his profile pic (the pic was a result of our inside joke), why?
Post Opinion