Twitter’s data model stores Tweets as a stream of records. When you delete a tweet, it stores another record which consumers are required to honor saying that the first record’s ID was deleted.
Twitter’s internal tools still have all of that data. In most cases the Internet Archive also does, too, which is how people have confirmed that, for example, the tweets in the famous “handled” email were nudes in violation of the non-consensual policy with no overriding news value.
There’s some selection bias here — the tweets we see in the thread are the ones twitter didn’t remove and the accounts twitter didn’t ban.
Twitter surely has the deleted tweets around somewhere, but it doesn’t seem to have been provided to the twitter files reporters.
https://twitter.com/mtaibbi/status/1603857596112330758