This is not the job of historians. Historians interpret the past. We do not try to preserve knowledge generally. The most we might do in that department is try to encourage people to preserve knowledge that might be of use for future historians — e.g., we encourage people we view as obviously important historical subjects (say, major politicians or scientists or entertainers or whatever) to make plans archive their correspondence before they die, and we sometimes conduct oral histories as a way of recording the kind of knowledge that doesn't get written down. But even then, there are dedicated oral historians, and dedicated archivists, who do that kind of work better than most regular historians do (and do it as their full-time jobs, unlike historians). Librarians, for example, do more for the preservation of books and databases than historians do.

I just bring this up because I think a lot of people confuse what "historians" are. We are not for the most part preservers of the past. We are primarily interpreters of the past. We rely on the work of these preservers — but we aren't them, most of the time. These are different professions and roles.