I also want to second this request. There are at least two scenarios that I encounter. One scenario is that I don’t want my clients to have insight into my workflow, and the other is that we sometimes need to give comments without identifying the person who does the commenting (because we as editors want to speak with one voice). I frequently have to delete all the comments towards the end and then re-insert them to avoid giving away this sort of information, which can mean as much as an hour extra work.
Please, please remove this stupid time stamp and other identifying information. As OP points out, it is also unnecessary clutter.