Reaching for the anti-salt
Sure, potassium is important, but don't fret too much about meeting a recent guideline.
Potassium is an important nutrient because it helps offset all the sodium that we get from salt, which, chemically, is sodium chloride. Potassium blunts sodium's tendency to increase blood pressure.
Potassium is important for another reason. We now eat much more meat, dairy-based food, and grains than evolution has equipped our bodies to handle. As a result, we end up in a mildly acidic state that's bad for our bones. Potassium in the form found in food is metabolized so it generates bicarbonate, which neutralizes this diet-induced acidity.