I’d be interested in hearing some more about the background to why this exists at all - seems to me to be a throwback to older generation forum systems. People who are familiar with them will like and be familiar with them, others coming from mailing lists or other backgrounds will find them distracting. I don’t care personally but do have to roll out discourse across a global community who come from various backgrounds and worry a bit about having to explain arcane stuff like this.
My guess is that this is about transparency - it’s good to have a record of who’s doing what and when to avoid confusion and disputes. If that’s the case then deleting the post is counter productive. Maybe a cleaner approach would be to keep this historical info about what’s happening to topics not in follow-up posts but in a simple log available somewhere else, e.g. in the summary following the first post in the topic.