Lots of high-profile actors are on twitter (tech influencers and politicans for 2 more examples) because it's such a direct, relatively clutter free way to get out information and have it seen.
Most politicians are still only technically on Twitter, continuing the Obama-era style of very careful and boring tweets. The only three I can think of that are 100% live tweeting like humans (regardless if they're humans you like) are AOC, Ted Cruz, and of course Trump.