When you are not a moderator and want to remove your old posts, the best way to do this is by “flag” “other reason” and then enter “please remove this, it is a dupe, outdated etc.”
When mods then remove the post, you will still get the concerning “community flagged it and it was removed” note, even though just you flagged it.
It would be good to have a different message here as this message is not correct.
Or even better a “flag” “request deletion” “state reason: xyz” method