Turning Twitter into WeChat is probably a bigger challenge than sending a rocket to Mars, but...
Yeah that doesn't count. Stuff you don't do doesn't count.
Similarly with Tesla, legacy automakers will electrify the world. Being a cheerleader on the side doesn't count.
CEOs are people who sign off quality of life for the people who buy the products/services that the company they lead is selling. And that is all there is to it. There is nothing tough or poetic about it. Sane people are scratching their heads at how some people are falling for the cult of the founder which started with Jobs.