I'm constantly surprised that no one has mainstreamed version control. I see so many cases where it could be applied: document creation and editing, web site updates, spreadsheets ... even the way that laws are amended in Parliament [1]
They're the most basic form of version control possible (little more than undo/redo). The Google one has a really awful interface as well. I haven't used any MS products in a long time, but Word's version control circa late 2000s was bad as well. Actual version control allows branching, merge strategies, offline editing, and all the other crazy stuff you can do with git.
Expressing all of that in a way that makes sense to end users is the real challenge, and I guess why this hasn't been solved yet.
[1] https://www.gov.uk/guidance/legislative-process-taking-a-bil... https://www.gov.uk/government/publications/amending-bills-st...