1. That repo is based on 250+ .go files and stores stuff as git blobs, which is obviously a much more involved, collaboration-focused approach than this tool's 1 .sh file and human-readable markdown files.
2. `tk` seems to be built with agent usage in mind from the jump. I'm sure `git-bug` is perfectly usable, but it's clearly not a focus.
3. The two linux package managers listed for `git-bug` are for (drum-roll, please...) arch and nix. Of course the latter can be setup on every (?) distro, but speaking personally, I find that to be quite the red flag for a devtool! I'm sure it's a bright green ones for fans of those distros/mindsets, of course :)