Just as news spread about Twitter removing accounts, Twitter realised they faced a major problem and decided they wouldn't go ahead with the mass purging on December 11 after all. In fact, this won't happen at all until Twitter figures out a way to memorialise accounts of those long gone.
It turns out many people were upset with the news as this means losing the accounts of those who have been deceased for years. As the purging meant losing even the history of what a person has posted on Twitter, losing precious memories or even important words and references for those who want to hold on to what has long passed.
Due to this, Twitter has shared that it was a miss on their part and that they won't be removing any inactive accounts yet until they figure out a way for people to memorialise Twitter accounts.
It's not to say that it won't happen, but it looks like this major Twitter purge won't happen anytime soon as it would take quite a bit of time to figure out how to memorialise old accounts, especially those who have already gone. With Facebook, you can set up for someone to take care of your account once you have passed on. Twitter doesn't have anything like that, not even a setting to have close friends.
But we shall see how this pans out. For now, all Twitter accounts, even the dead ones that should be purged, are safe.