Warren Buffett is a billionaire, a level of wealth that simply wouldn't exist in a fairer society. However, the context that's missing is in the same conversation he also said "How can this be fair? How can this be right?" in reference to his tax rate vs his employees. Again, just for clarity, no billionaires should exist. At $999 million dollars, their remaining wealth should be distributed among workers, and a park named after them...
https://www.snopes.com/fact-check/warren-buffett-class-warfare-quote/