He also doesn’t feel the compulsion to be the main character - Zuck has those platforms because it’s his business. Musk bought Twitter in part to be a platform to mold at his own whim and amplify himself as a public and cultural figure.
Zuck also doesn't appear to have low self esteem and doesn't really care what people say about him or make fun of him.
I'm in a few meme groups and there are always memes make fun of Zuck, probably daily..