Our team is all default ON, but nobody is shy about turning it off if they need to do something that might be distracting or just don't want to be on video for any reason. It's a lot easier to visually signal agreement / disagreement in conversations that way without having to use your voice.

I'm always default ON when meeting with people outside our company as well. if anything because I'm used to using body language in conversations and it seems to move things along more naturally than it would with a phone-style meeting.