I think you're trying to fabricate problems where there are none.
Git's UX problem lies in the way it's CLI is not intuitive for those unfamiliar with it, but a) using GUI frontends like SourceTree allows newbies to eliminate that issue, b) with time you onboard to the CLI and everything just works.
At best, your suggestion to use another user interface is equivalent to suggesting Git users to adopt a new GUI frontend that's polished in a different way.
> Git is _incredibly_ complex to understand,
I don't know what you can possibly mean by "incredibly complex".
For end users, your mental model can be limited to a) you clone a repository, b) you commit and your changes, c) you push your changes to make them available to everyone, d) you pull everyone's changes to have access to them.
This is hardly rocket science. I mean, why do you think Git managed to become the world's de facto standard VCS and sets the gold standard for VCSs?