People don't feel guilt online, generally, because they either forget the person they are talking to is a vulnerable human, or they just imagine them as someone deserving of their vitriol.
However, as soon as they are sat in front of someone and are picking up on the visual clues in facial expressions and body language which make it clear that what they are saying is actually affecting a real person with feelings, almost everyone has a profound sense of empathy or guilt.
However, as soon as they are sat in front of someone and are picking up on the visual clues in facial expressions and body language which make it clear that what they are saying is actually affecting a real person with feelings, almost everyone has a profound sense of empathy or guilt.