Speaking ill of others says more about the person stating their prejudice, judgments, criticisms, and denigrating another. If you are listening to someone speaking badly of another in all likelihood they speak badly of you too. I think it’s a learnt pattern of relating. Becoming aware that you do it is the key to changing how you relate. Plato said, ” Great minds speak of ideas, mediocre minds speak of events, small minds speak of others.” ~ Elizabeth Painting
Say nothing if you have nothing to say. Learn to love n respect oneself before expecting others to do the same for you.