The time the characters take to reply may sometimes indicate much about how they are feeling about what you said. Also, some messages can be deleted by a character, and if you speed it too much you might not get to see its original content. They also hesitate when typing, make pauses, delete what they were gonna say for sooome reasons... Also, the speed at which the text is shown during the calls also marks the speed of speech, which helps to imagine the intonation, the character intentions and feelings... The timing of the messages is a big part of TYL's storytelling 😊