I built this primarily because I was bored in a Zoom lecture and wanted to chat with other people in the class. There were a couple of small group chats that started spontaneously but I thought it would be more fun if the entire class could be involved. (It doesn't have to be anonymous but otherwise the professor or TFs could see who isn't paying attention in class!)
As a prof (fortunately one who is not lecturing this year) I always wanted an easy method for students to anonymously ask questions. Maybe they will push it onto the students!