We used for some time something akin to this in my previous job, and it has its ups and downs (most of what you listed are the ‘ups’, for certain, and in that manner it had a useful purpose).
In my experience, sometimes you do so much during the day that you constantly forget to list things (especially during hectic days), and it’s easy to feel that ‘you did nothing’ or see little value in tasks you completed, as they are normal and ‘part of your job’ to you, even if the value they add is there. Also, stopping after you finished to list what you did sometimes took you out of your “flow”. Since I used to work closely with a group, it was honestly easier to ask each other what we did during the day and list that, as others tended to include small things you give for granted.
The opposite occurred to us during ‘calm’ days: people tend to overexplain simple tasks they did because there is this sensation of ‘I need to fill the log and make it look nice and bulky’. Also, for those who are not fully aware of what completing your tasks implies, they can overlook the amount of time and effort it takes to do the job and easily misjudge it (“oh, they only did this during the day?” and you actually had to work during lunch to complete it in time… real story btw).
In our case, in the end we decided to remove this practice as it fell closer to a micromanagement style we were against.
Those are my two cents, hope it helps!