Warning! The following contains spoilers for Star Trek: Picard's Season 1 finale. Read at your own risk!
Star Trek: Picard had a pretty wild finale that made massive changes that will impact the franchise's future, but it also closed the door on stories that hadn't truly reached satisfying conclusions. Specifically, the CBS All Access spinoff set the stage for a true reunion between Jean-Luc Picard and Data, who had not spoken since Data sacrificed his life in Star Trek: Nemesis.
The two beloved characters had a chance to share all their unresolved feelings with one another, and Data was able to ask Picard for one final favor. He wished for the last remaining bit of his consciousness to be removed from existence, so that he could experience one thing that's truly human, a finite life. Patrick Stewart spoke to THR about the scene, and what it meant to shoot such an emotional wrap-up with longtime co-star Brent Spiner.
I was looking forward to shooting it so very much, because I adore working with Brent. But the content of this scene was so serious, and so important to the characters — and the affection and mutual respect — was so clear and so strong. Picard knew that this would probably be the last time that he was ever with [Data] and we — we had to address that. The guilt Picard felt over Data's loss at the beginning of the season, that the two characters never had a proper goodbye, or resolution, in [Nemesis] ... We took almost the entire day, not quite, as I recall, [to shoot the scene], but it was a very, very intense experience.
Filming the scene meant so much to Patrick Stewart that he requested to go home with the chair Jean-Luc Picard sat in during his goodbye to Data. Stewart said he wanted the chair because of the moment's significance, but also joked that it was pretty comfortable, too. The chair is indeed now sitting in Stewart's home in Oxfordshire, provided he brings it back to set should Star Trek: Picard need it in the future.
Shooting Data's scene was about more than the emotional payout however, it was about concluding an arc for Data that was open-ended. Akiva Goldsman told THR the purpose of the scene was a sequel to the events of Star Trek: Nemesis, and gave the character of Data a conclusive arc.
Star Trek: Nemesis both furthered and abrogated Data's arc. He didn't get the full closure, so Data's arc was sort of continued by Nemesis, but also stopped prematurely. We spent all those years with the character wrestling with the nature of what it is to be human. And he needed to complete that journey. And we wanted the season to aid him in that. To also help give us a chance to bring Picard's arc to a conclusion, at least when it comes to the Picard that we knew
Data "died," and in a stranger twist, Jean-Luc Picard's mind was transferred into a Synth golem. Picard won't have all the augments that a usual Synth would, but he also won't have to worry about that debilitating brain illness, and will presumably live out the rest of his days in good health. There's built-in tech that will ensure he dies around the same time he would without any major illness, so Picard is feasibly guaranteed not doomed to repeat Data's troubled existence in the years after Star Trek: Nemesis.