Really? I know a lot of teachers that are atleast up to date or know a lot about student relationships and a lot of students usually find out teachers personal lives too especially with social media today.Completele divergence here, but I have experience teaching.
You often struggle to maintain respect because you genuinely care for you students. In the Church, we know full well what happens when CLEAR boundaries aren't set. Students being involved in teachers' personal affairs wouldn't fly.
In a funny note, this manga has this weird dynamic of teachers using physical violence as their means to make students respect them (to varying degrees of success) lol