A PNG-Tuber (aka V-Tuber, GIF-Tuber) is a great, alternative, way for content creators to be "present" within their streams & video content without having to show their face. There are many reasons why a content creator may not want to reveal their face ranging from safety to possibly aiming for a specific style/theme for their brand. V-Tubers have grown exponentially within the last year to the point of even being interviewed on live television, so it's certainly beyond just a trend now.