The horror of a casual teacher

That's the most chill looking mannequin I have ever seen

This mannequin reminds me of my old english language teacher. He was the best teacher ever, but when he couldn't be bothered teaching (like at the end of term) he would just stick the Inbetweeners on and be like 'yes look at the different names these kids call each other'. And, for a project where we had to study language, he was like 'if I had to do this project I would do it on Arctic monkeys songs' and then proceeded to spend the rest of the lesson showing us his favourite arctic monkeys songs

In my country we call our teachers by their first name and I think that helped me understand that they’re just people, like me and everyone else in the world. So now that I go to an international school where we are supposed to say miss or mr I feel like it’s just building an arbitrary wall between me and the one I’m supposed to trust and respect. I know not a lot of people disagree with me on this but I just feel like it’s easier to try answering or asking questions to someone you speak to on an equal level. Teachers that saw me as a person rather than just a student got me out of my shell when I was younger.
People who dislike using their teachers first name, could you explain why? I’m genuinely curious.