That's terrible. Everyone who is saying "We need to be harsher with kids", this isn't being harsh with them it's bullying. My Latin teacher whom I had for 3 years was "harsh" and "realistic". however he also had discernment, he was able to tell when a student would truly be upset by being called a "worthless sack of excrement" (one of his favorites)and he wouldn't be so blunt to them, he also gave you praise when you really deserved it.
he was wildly popular within the Latin students.
As a side story one of my favorite moment is when he called out a section of class, we were going over vocab and this group of kids who always fail and disrupt his lectures were being jerkasses like normal. he shut the book and said
"You know what? Forget it. You guys only need to know 2 vocab words for the rest over your life, "Paper" and "Plastic""
It was awesome.