Warning: SPOILERS for Star Trek: Picard Season 3 Finale – "The Last Generation"Star Trek: Picard season 3's finale tacitly explains why there has been no mention of the Borg in Star Trek: Discovery's 32nd century. "The Last Generation" featured the final conflict between Admiral Jean-Luc Picard (Patrick Stewart) and the Borg Queen (Alice Krige). Picard and his crew of the USS Enterprise-D dealt the Borg their final fate by rescuing Jean-Luc's son, Jack Crusher (Ed Speleers). The defeat of the Borg liberated the assimilated Starfleet, which saved both Earth and the United Federation of Planets from total destruction.
The Borg have been the Federation's greatest enemies since their introduction in Star Trek: The Next Generation and they were a mortal threat throughout the late 24th century. The Borg threatened to assimilate Earth multiple times, including in Star Trek: First Contact, which introduced the Borg Queen. However, the Borg were dying in Star Trek: Picard season 3's finale as a result of being "poisoned" by Admiral Kathryn Janeway (Kate Mulgrew) in Star Trek: Voyager's finale. Assimilating Starfleet with the help of Star Trek: Deep Space Nine's rogue Changelings via Jack Crusher, who became Vox of Borg, was the Queen's last-ditch attempt to evolve the Borg and propagate her species.
