Would your answer really turn on whether the observer had imperfect memory? What if they had photographic memory?
Think the retention period for ad tracking is only a few months or years - probably because storage is too expensive these days and there isn't a terrible amount of value in keeping raw data forever.
I will naturally forget because I’m a human with fuzzy memory / storage.
I am not an highly consistent, available and resilient database which will store the information for the next 5 / 10 / 15 / 30 / N years.
Appreciate this is a bit of a nit pick on your argument, but I feel it is also important because it highlights the massive risk / impact difference.