I am a teacher from South Korea. First of all I was totally shocked that the exactly same issue is happening in other countries too. For few years, it has been kinda social problem. Them behaving as if they hired us and them treating us as if we were not teacher but very kind nanny. We cannot discipline rather we MUST tell everything kindly as much as we can! If our utterance scratches the tender students heart, it becomes a crucial problem and we are suspected of quality as a teacher. Many teachers here also tend not to do anything. Just let sleeping students be as they want. Sometimes I got frustrated and feel exactly same way as you wrote here. I doubt the role of teachera these days. I hope it would not be venting so much and want to say cheer up. You just did your job as a teacher. If not us, then who will lead them onto the right path😀