Some time ago there was dismay on Mastodon (and Pleroma ?) instances about data scraping. Before that happened there were privacy concerned people automatically deleting their own toots, limiting them for example to the latest toots for thirty days. With Lemmy things are different since Lemmy is a link aggregator rather than micro blogging, and Mastodon has boost option (Called replay with Pleroma ?). However deleting your older comments (but not posts) automatically would be really nice for privacy reasons.
Deleting Comments is bad, since your Opinion or Knowlege might be important for someone or yourself in the future. A better way to decrease a digital footprint is the ability to post things anonymously. This comment should not be tied to my account. Anonymous posting also brings other benefits like a bigger engagement. I really liked FlowChat from @dessalines@lemmy.ml
What about having an option to “post anonymously”, and only mods of that community and instance-admins can see the author?
Anonymous comments would be best, but only if it’s integrated with upvoting/downvoting/flagging to provide personalized ranking of comments.