I’m getting annoyed with people that ask a question, have the community answer their question and troubleshoot over several days, only to delete their post and the solution.
The person asking the question is often providing the least amount of effort, so why should they have exclusive right to delete the contributions of others?
Possible fix: have a per-community option to only request deletion.
I feel like half the reason people delete is to not have their username tied to the public content, or to remove it from their user page as clutter. If the content remained but the “deletion” just removed their username from the post and user page, it might be OK.