That's never been true in politics or with Bernie himself. His character, how he does speeches, what things he does which endears people to him, his charisma etc are all vital to how he gained followers. No politician runs strictly on message or policies, it's literally impossible to do so because Bernie's existence is not something we can ignore.His message and policies will build his coalition, or they won’t. A personality-driven Left movement gets us absolutely nowhere, a lesson we SHOULD have learned with Obama yet somehow have not.
He has popular memes for his base to signal boost with! You think this didn't endear him to people?