1. Progressive used to mean something different than it does now. Progressives (Teddy Roosevelt) used to believe in the power of economic progress as a benefit to society. If business got in the way, then the government needed to step in. Now progressivism is about advancing specific social agendas, and pushing for government social interventions. Musk is a progressive in the former sense.
2. Twitter is perhaps on the way out, but Musk’s view on maximizing free speech is relevant and consistent with his version of progressivism. He explains that the more people can speak their minds, the more likely it is that the best ideas will emerge. He also suggests that it is also likely that this human interaction will be to the benefit of the AI corpus.
I’m not a Musk fan, but I find it difficult to disagree with these points.