Have you ever visited an unmoderated sub? Without moderators, reddit would turn to shit instantly.

That’s a non issue. You just cannot expect to be able to delete anything you post on the internet. Even the great reddit with the awesome deletion feature cannot help you. You might be able to delete your comment there, but there is https://www.unddit.com/ https://archive.is/ https://web.archive.org/ and many others, where your comment will still be available.