Musk realized that Democrats, and more specifically their Marxist, "Woke Mind Virus" inspired policies were literally driving the US economy and political system off a cliff.
He bought Twitter, that was operating in the red, at great personal financial risk to save a public free speech platform from what was increasingly being subjected to a very dangerous public/private government moderated censorship cooperation. Then, he joined with Trump in an effort to stop what he accurately saw as unsustainable deficit spending and contributory waste, fraud and abuse. That, by the way, hurt him also as Trump discontinued electric car subsidies which had greatly benefited Tesla.
Overnight, Musk went from a darling of the left, where everyone wanted to drive a Tesla to a piriah.
Reality: While admitting that there are legitimate socitial and economic inequities that need to be addressed, if you look at Democrat policies they are almost all "feel good", virtue signaling based that effectively won't work and any rational analysis proves they will lead to decline or outright collapse. There are countless historical examples supporting this statement. For a party and members, including the Propaganda Media, who see themselves as a well educated, lofty, smarter group as opposed to the Republicans, who they often refer to dissmissively as "smelling of Walmart", clinging to their Bibles and guns, it's difficult to understand how they can suffer from what could be characterized as an irrational mass hypnosis.