It was modeled after “deep work” sessions I have participated in the past (with non-colleagues) where saying what I worked on at the end was a useful reflection

It was modeled after “deep work” sessions I have participated in the past (with non-colleagues) where saying what I worked on at the end was a useful reflection and to get in the habit of not (e.g.) getting sucked into responding to an email that came in during the session. I can understand the skepticism of it, but the value is in writing them not in reading them. It's not required and some people don't do it.