There seem more references to Timeline and continuity between devices, than this:
Microsoft 'Timeline' for Windows 10 Fall Creators Update lets you rewind open apps and documents | Windows Central
which seems to offer a quite different definition but which does seem to fit the name better.

At this point all is speculation, I would think. From MS's point of view, continuity between devices would seem to offer a greater market advantage- or perhaps response- as it would tend to persuade people to use Windows devices to gain the benefit.

Providing a slick version of File History would be nice, but far more arcane, applying to a niche market of informed users, so much less significant in market terms.