A lower interest rate means less returns for people who earn money off interest.
Now the Fed only controls one of the many interest rates that are out there. But the one that the fed controls can influence the others, so a lot of really wealthy folks and institutions are going to see lower returns. It's the kind of thing that should be right up Elizabeth Warren's and Bernie Sanders' alley.
The rates are supposed to be changed in response to something going wrong in the economy. But nothing appears to be going wrong right now. Jerome Powell says he is doing this proactively because he sees a high risk of something going wrong soon. I don't think that's how it's worked in the past. I'm pretty sure they are supposed to be reactive, rather than proactive.
I think that a lot of what's gone right in this country since the early '70s is Fed policy. They've had the freedom to go against what the people want and they have won the confidence of the rest of the world that we will have the most stable currency. I feel like if the world starts to perceive that we change our interest rates based on how voters feel, they will have less confidence in our currency.

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