But with reddit, you can also roll through every last comment you ever wrote and delete them (as it should be; you own the copyright to those comments):

Reddit History Wiper http://userscripts.org/scripts/show/111025

You have granted Reddit a perpetual license to them though, so they can keep them if they want

> you agree that by posting messages, uploading files, inputting data, or engaging in any other form of communication with or through the Website, you grant us a royalty-free, perpetual, non-exclusive, unrestricted, worldwide license to use, reproduce, modify, adapt, translate, enhance, transmit, distribute, publicly perform, display, or sublicense any such communication in any medium (now in existence or hereinafter developed) and for any purpose, including commercial purposes, and to authorize others to do so.

^Reddit copyright policy

Reddit still gives you the ability to delete your comments at any time. Hacker News does not.

You misunderstand how reddit works, the comment can be deleted as well. This leads to a fairly common occurance of people asking what was said to generate the responses.

Ah you're right, what I was referring to was what happens during account deletion.

I would love it if sites like Reddit took this a step further and used stylometry obfuscation techniques in addition to removing the name on the account. We desperately need tools to help make content as anonymous as possible after the fact, but still retain the essence of that content so that conversations that are a public good can still be maintained for posterity.