> the REST inspiration leaves me feeling underwhelmed; there has to be a more human-friendly model.

Jujutsu VCS! https://www.jj-vcs.dev

It doesn't use Git primitives directly, but it has Git interoperability using semantically more powerful primitives. (e.g., there is not only one index -- you can perform rebases, amends, squashes etc. remotely (without checking out first) -- conflicts are non-blocking and support n-way merges -- and so much more)

I've embraced it to the point of porting complex agentic frameworks to support jj (https://github.com/LoganDark/get-shit-done) and I do not regret it at all. Jujutsu is my absolute favorite VCS now.