Modern campaigns need access to a trove of videos, sound clips, and speeches - together with transcripts - of their candidate and their opponents’ appearances. Such an archive is invaluable for opposition research, rapid response, and related activities.
This idea is described at a high level by Matt Hodges in this post, based loosely on the Biden campaign’s research archive, called “CouchPotato”. Brett O’Donnell also mentions this idea in his Business of Politics interview, at 25:21.