I primarily use GitHub CLI to interact with the GitHub API, not Git. I don't really see it as an extension of the Git CLI, which I use much more frequently. Everything you can do with it can also be done through their REST API.

I use it for things that aren't really git features, like:

Syncing repository admin, pull request, and branch control settings across multiple repositories

Checking the status of self-hosted actions runners

Creating pull requests, auto-approving them