If you need a solution immediately, you can scrub the entire edit history for that post. Delete the key post:<pid>:diffs and all keys that start with diff:<pid>
e.g. redis-cli keys diff:123.* | xargs redis-cli DEL
I want posts in a certain category to be deleted after a period of time such as one year.
Can I do it with nodebb?
Not avaiable out of the box, but you can use something like https://github.com/julianlam/nodebb-plugin-archiver or modify it to delete the topics instead of locking.