My first riding instructor was a screamer. It was a real testament to my love of horses and riding that I endured the verbal abuse and kept coming back for more, but it was not a productive learning environment and who knows how much faster I and my fellow lesson kids would have progressed in a less stressful more pleasant environment. Fortunately, eventually the screamer damaged her vocal cords and was forced to quit. She was replaced by a lovely young woman who, somehow, managed to successfully teach and produce good young riders without yelling, screaming, or belittling her students.
Honestly, I’m a little shocked at how many people posting here seem to think it’s OK to scream, shout, berate, and belittle students. Does it happen? Yes. Do coaches of other sports and even parents do it? Yes. But that doesn’t make it OK.
Now, as an adult in charge of my own life, the first time a trainer screams at me and treats me disrespectfully is the last time I ever ride with them. If I’m taking lessons, it’s because I have a sincere desire to learn and improve. If I’m not doing what you’re telling me to do, it’s because I am physically unable to do so or I don’t understand what you’re asking. Yelling at me isn’t going to accomplish anything besides deeply pissing me off.
OP, you’re going to have to do whatever feels right to you. No one else can make that decision because we each have our own reactions to, and tolerance for, what you’re experiencing and observing. Like I already said, I don’t put up with that crap. But that’s me.