We have no idea how much Ethereum Vitalik Buterin is holding right now but at point he disclosed that he was holding 355,000 ETH  but during the course there were reports that he sold billions of dollars worth of ETH and there is no clarity regarding how much he holds now and this year there were reports that he moved billions of dollars worth of ETH and even if he sells them unless he reveals no one is going to know about it  .