I agree. You laid out my current design in a nutshell, actually. Except for folders. But my branches will be more than a bookmark.
However, I was going to make a browser UI from the start. I could implement a branch and file explorer in that UI, which would allow you to do the same thing.
Would that be good enough or not? I'd love to know because I want to build this tool for humans first.
I do think that Git is very well established, and it would probably take a major player, maybe Azure or AWS with a cloud-based IDE to change paradigms.
I just realized something: maybe I can make it so regular file explorers work.
I had intended to use something like Fossil's checkouts. I could formalize it; each branch the user wants could be a separate directory in the repo directory.
While I hate that, people seem to like it. I think I will do it.
Thank you for pointing me in the right direction.