if we tax the super rich then the list of extremely powerful people will be one item long: politicians. i think its telling that they are going after rich conservative people rather than break up blackrock et al.
That sounds like a good thing to me. I would prefer the people who hold power in our society be the ones democratically elected, not the ones who lucked into a leviathan amount of money and can now buy Twitter for fun.
Separation of powers is a very important reason not to limit the power to just politicians. Just like how we would prefer not to have media moguls also be politicians, leaving control of the media to just the government is a bad thing for democracy as it just compounds power towards the existing holders.