Thing is, most people use what they THINK is brutal honesty and use it when it’s really just negative opinions they feel the need to tell someone else for whatever reason.
If you know the person well enough to know what they need to hear, you should also know them well enough how to say it in a way that’s effective. That would be compassionate honesty.
If you start the sentence with “I know you don’t wanna hear this but”
there’s a very good chance the ears of the other person will close up. It’s ineffective.