iiuc it supported a nicer workflow than git did, but that’s not out of the ordinary as so does Darcs, Pijul, Jujutsu, Mercurial, etc. git is just “good enough” for people to put up with the rough edges, rather than learn a new tool that never has them to begin with.
It just never had the dev mindshare to catch on, it’s been a GNU project for over 18 years at this point and that hasn’t helped.
From my knowledge, outside of an odd recurring example, that’s generally how Dr. Who works.
Feels like it’s getting into the weeds a bit, but the approaches to the idea of a multiverse in the properties goes a way to handle the issues with canon. Trek has quantum realities, where any event can just be said to happen in a different plane and not affect the main one. Dr. Who however has a single shared timeline and relies on time travel to write events into and out of existence.
So when the 10th Doctor met the crew of the Cerritos? In Trek that’s just a different continuity to the main story, but in Dr. Who it’s currently the reason why the Doctor doesn’t have 3D glasses anymore (He left them behind and Rutherford found them).
Edit: Oh yeah, how could I forget? the Guardian of Forever can also cross over into alternate dimensions and move people between them.