@jemostrom I have the same experience. A few of my students speak up in the large group but it’s pretty much the same students that used to talk the most in lectures on campus as well.
In smaller groups it works much better. The breakout rooms of Zoom is a nice tool for that.
The chat is a different beast. There they tend to be quite chatty. Lot’s of good questions, and sometimes answers to each others questions, and also quite a lot of internet humour, text based memes, etc. In one lecture I had to tell them to back off on the silliness in the chat so valuable questions and/or answers didn’t disappear in the flood of jokes.