I try not to harp on Girard's mistakes, and if I do bring them up then it's always with "He's young and still learning, he'll likely get better than this." I will always give young players tons and tons of rope because I got into hockey by watching a development league before I ever gave a crap about the NHL. Hell, I still believe in Jost.
That being said, I bring up Girard's mistakes usually to point out that the notion that Girard and/or Makar are absolutely capable of replacing what Barrie brings is just incorrect. For all of Barrie's mistakes (and I'm not going to speak to his attitude beyond pointing out that forcing offensive defensemen to change their game so that they're better at defense at the expense of offense never ever works), he brings positives that Girard simply can't touch right now.
Girard is going to make mistakes. Makar is going to make mistakes. Barrie makes mistakes all the time. With offensive defensemen, what you hope is that the good outweighs the bad, and there's no question that's true for Barrie no matter what some other posters say. Right now for Girard, the good is more potential than anything else.