Why does someone say “To put it bluntly” when they’re going to say the hard truth?

I mean is it that necessary?

My best friends called me out for being very annoying and passive aggressive.
My guy friend said, “No guy wants a passive aggressive girlfriend that is a yes person all the time. Your boyfriend wants you to have you OWN opinion and he shouldn’t have to drag it out of you! That’s low.”
I was like, “What do you mean by passive aggressive?”
My female best friend said, “To it bluntly you’re annoying the sh*t outta him. That kind of act will drive him away and he wants a girl that’s brave enough to voice her own opinions and not afraid to disagree and you’re not doing that!”
I stood there shocked. I was like, “Wow girl that was.....harsh and hurtful.”
Then she said, “Girl whatever. You asked for an honestly and as your best friends we gotta call it as we see it!”
Guy friend, “Right. Best friends don’t sugarcoat nothing.
My best friends can be so brutal sometimes.