You want simple internals, and one would expect programmers to understand those internals. You want the userspace to do obvious things with those internals. You don't want magic in between. Understanding internals is a feature, not a bug.
I picked Debian over Red Hat since, at the time, I could understand how .deb packages worked, and look over the state of the system. Red Hat had more opaque internals. If something broke on a Debian system, rare as it was, I could go in and fix it manually. If something broke on a Red Hat system, it was generally in a binary database file, and meant a reinstall. Red Hat also broke more often, I think for very similar reasons in design philosophy.
If I were making a tool for grandma to manage her photos, that's be something different. If you're making a coding tool for 3rd graders, perhaps you want to hide more stuff too, but even there, many modern coding environments translate blockly into Python/JS/etc. code, and show the code to kids so they can see under the hood.
I have a car, and as a car user, I want thinks to just work. As a car mechanic, I'd like things to be understandable, fixable, documented, and transparent.
git is like that. It has simple internals. Once you understand them, the userspace become very understandable too. The upsides of the elegant internals far outweigh the downside of a slightly clumsy userspace, which is why it's the dominant VCS right now.
It took over precisely from things which "just worked" with a simple userspace, and clumsy internals, like SVN and CVS.