I think Phyrra is still a valid thing to adress, in a different manner than hurting Jaune though.
She was the best of them, and perhaps she still is. She was noble, driven, brave and selfless, with all the skills needed to back it up and more. She was a hero through and through.
She was the best... and all she did was bravely run headfirst into a pointless death.
That's just it. One of the most promising lives cut short, because all that was in her mind was stand her ground and fight the great evil, going against Ozpin's instructions to get help instead. She gladly and knowingly ran into a martyr's end. I can help but see the parallels between Phyrra at the end of volume 3 and RWBY/ORNJ against Salem in Atlas. Barring the inevitable Deus ex Machina, this seems headed right into the same direction.
What I'm gathering from this situation is that not only is Ren not going over the line with his words. He's not going far enough. It's not just that they weren't ready to be huntsmen, it's that being huntsmen aren't what's needed in the situation eiither. All huntsmen that don't also occupy a position of authority are ultimately just muscle, brilliant when it comes to going through a combat situation, but falling flat on their faces whenever it goes beyond that.
Let's not pretend that Ruby and her friends are not ultimately a gang of murderhobos barely entering adulthood, who have taken it upon themselves to decide the fate of nations. "Way over their heads" is right, and it worries me that Ren is the only one who has stopped to think about this, only to be blown off, specially when I can already see him being inspired into being a believer again, once the angst passes.