changing your users ID (nickname) to another has noting to do with any "right to be forgotten", and if we ever are forced to implement "the right to be forgotten", it will simply mean that a forum manager (NOT a moderator mind you) upon request (a carefully checked request, because we don't want any complaints afterwards) gets the ability to wipe all posts from a user from the database. AFAIK this has never happened up-to now. and I don't know if its even possible.
for now, a moderator can only delete posts manually one by one, and we actually (and reluctantly because it can be a lot of work) only do that when the posts are changed into spam by a spammer that managed to get in some posts, then post edit them by inserting spam URL's.
We don't like to delete random posts in a thread because we don't want to damage valid threads, which invariable happens, because users invariably reply even to fake spammers posts. note that spammers are only interested in finding ways to insert spam posts with a minimum of effort on their part, so their posts won't have much actual content. that is why we try to give spammers no way in, or if they slip through, delete their posts before regular posters can reply.
now by popular request i'm locking this thread....