Trump had the same power when he was in office (and still allowed on Twitter!) - when he tweeted, we would see substantial movement in the US Dollar and also in safe havens/ fiat like Gold etc. From a trader's perspective, it was a nightmare but very interesting nonetheless.
Something interesting about Elon Musk in particular is the almost cult-like following he has developed, with whom he holds absolute unwavering status and respect. I think the fact that we've seen so many examples of the symbiotic relationship between social media and the markets does suggest, to me at least, that it is a powderkeg which is already showing signs of blowing up (e.g. Gamestop). We're in for a really interesting period in the next few years in terms of how this is approached by regulators.
