Interactive rebase? There's no GUI that actually does that well, if at all. And it's a massive part of my daily workflow.

The CLI is far, far more powerful and has many features that GUIs do not.

It's also scriptable. For example, I often like to see just the commits I've made that diverge from master, along with the files changed in each. This can be accomplished with git log --oneline --stat --name-status origin/master..HEAD. What's more, since this is just a CLI command, I can very easily make a keybind in vim to execute the command and stick it's output into a split window. This lets me use git as a navigation tool as I can then very quickly jump to files that I've changed in some recent commit.

This is all using a standard, uniform interface without mucking around with IDE plugin settings (if they even can do such a thing). I have many, many other examples of scripting with it, such as loading side-by-side diffs for all files in the worktree against some particular commit (defaulting to master) in vim in a tabpage-per-file, which I often use to review all of my changes before making a commit.