Please add a feature to 'edit' messages with random data rather than redact. This has the advantage of not only updating the 'live' database but also if it's backed up in the future they'll only have the garbage data and not what you actually said.
Being able to overwrite history (where possible) is extremely valuable that reddit/discord let you do.
Additionally, there should be a 'spoofer' mode, that randomly makes comments, uploads multi GB files full of random data and adds noise to further enhance privacy.
I take great joy in "abusing" text areas and file upload boxes on the internet - it makes it significantly harder to track a subject in any way when you are making 1000 comments a day, uploading 10,000 photos you found randomly online and are joining 50 different channels ;)
To be honest I should probably make a script to do that, especially on HN...