Ethereum co-founder Vitalik Buterin has called on Elon Musk to "lower the temperature" as his platform sparks a new free speech controversy amid a heated debate over foreign tech workers. In an X post on December 31, Buterin said that while he admired Musk's willingness to fight for free speech, he asked the Tesla CEO to "lower the temperature", tone down the "tone of his words" and stop using the "social media banhammer" to shut down the X account.