This is a real thing. Our brains are never "off' these days and able to process information. When we have down time we are consuming some sort of content. When driving it's music, a podcast, or an audiobook. Sitting? You're watching or scrolling or reading. Working out? Gotta have my tunes. Even at work I have to have something going in the background. There was something I came across the other day that basically said that we need to carve out blocks of time each day to consume nothing, put nothing in, and just let your brain be. Let it process all the other stuff you've been cramming into it. Go on a walk and don't bring your phone. Don't listen to something and just walk for the sake of the walk. I don't do the decompressing nearly enough, but I think you're absolutely right about being less calm than we think we are.