I enjoy deleting my old posts and comments, but it’s lot of work doing it individually, especially with comments. For other platforms there are apps you can login with, then delete old or all content, but I can’t find one for Lemmy. Does such a thing even exist?
I’ve found edits don’t federate consistently.
Given that so much depends on the implementation details of the various instances I’m not sure anything more than a “best effort” is possible.
I wouldn’t post anything that would be a problem.