Sometimes I write in the youtube comments. I call it constructive criticism but, is often perceived as hate. For instance, many tubers have background music while they are talking. I find that annoying. Many would say, "you don't like it, move on". Thing is, I liked the content. But, I moved on. Maybe one less viewer doesn't matter. Maybe, he gained many viewers because of the raunchy noise in the background.
Many car builds, the presenter has the camera pointed at his face for 5 minutes while talking about his build. "Point the camera at the car and talk". I made such a comment and was slammed for it. I don't watch that channel anymore. Maybe one less viewer doesn't mean anything.