The last published DPC audit found that it does [1]. There's really no reason to subject themselves to huge fines and lie about it, a very small fraction of facebook users delete anything.

The "data dump" you're referring to was probably scraped from public facebook pages before you deleted the account. There has never to my knowledge been a case of private data becoming public that was exfiltrated from facebook proper.

[1] https://web.archive.org/web/20171218060100/https://www.datap...