I disagree there are so many other ways to be funny than making fun of someone's stuttering. We shouldn't be bullying people delivering trillions of dollars of value to society.
And yes, it is indeed because he's a billionaire actively shaping a worse society. Not because it's okay to make fun of impediments when it's on rich people.
But he's not being bullied and being harassed. He's a public figure and he has fuck you money. If he doesn't like people making jokes about him, he can simply shut up, disappear from public space and live comfortable life without ever working again.
Surely, you mean trillions of dollars of negative value?
Sure, but what about the people who consume trillions of dollars of value?