Would you punish your child or talk to them

My kids are very good kids who don't really get in trouble. My son(16) got sent to the principals office for being disrespectful and got 5 demerits. He's deaf and has cochlear implants. He can hear with them but he talks and signs at the same time. He started this new school after winter break and he was complaining to me about one of his teachers talking down to him like he was a small child and that she also insinuated he couldn't read well because he's deaf. He got in trouble because he said she was talking down to him and he told her "I'm not gonna respond to you if you keep talking to me like that. I'm 16 not 6. Talk to me like a person." She didn't like how he spoke to her and they started arguing and he told her in front of the whole class that her being uncomfortable around deaf people isn't his responsibility. She said she wasn't uncomfortable with it and he's being disrespectful and maybe instead of being disrespectful he could educate her. He said "If you made it all the way through a bachelor's degree without knowing that deaf people can read than maybe go back to school and get educated." Then he got sent to the principals office. My husband wanted to ground him right away. I think because he's never been in trouble before I wanted to talk it out. I told him that his feelings are valid and I can't say I understand. Idk what it's like to be talked down to for having a disability but we have to handle things differently. I told him the right thing to do would be to talk to his teacher in PRIVATE about how he felt. If he didn't change and he needed me to step in I would but there are other steps to take before going off on her. We had a meeting with the principal today and they both apologized to each other. My husband thinks I'm too soft with the kids. I just think if this is abnormal behavior for them then before jumping to punishment I wanted to talk it out. Obviously if this becomes a habit he will be punished but I just wanted to worry about finding a solution instead of punishment.