It's because people have gotten addicted to getting internet backpats for morally grandstanding over cartoon characters.
EVERYONE with a properly functioning frontal lobe and emotional intelligence knows that these things would not be ok in the real world. No one is saying that it's cool for real students to hook up with their much older teachers. No one is saying "real rape is cool actually" unless they are saying it for the shock value or to purposely upset people who cry about it happening in fiction.
It's more concerning that these people express more concern for fictional characters than they do for the real people they harass, degrade and slander.
Idk why ppl are calling the teacher pedo when its still only one sided crush from the student… and i think this type of stuff is fine as long as u know that its wrong in real life idk