Sugarcoat it enough and the message melts. Sometimes kind means clear.

Softening has a limit past which the message stops existing. Add enough cushioning and the person leaves with a pleasant feeling and no idea that anything needs to change, so you spent the conversation and got nothing for it. Kindness includes making sure the thing arrives. Clarity and warmth are not in competition.

State the point in one sentence, early, and let the kindness live in your tone and in what you do afterward. Then check what they took away. If they cannot repeat the main thing back, it did not land, however gently you delivered it.