That's the bare minimum of what you can do, which really just constitutes dumping your code on GitHub, slapping an unmaintained label in the readme, and calling it a day
But we can go beyond that, and start to do more work, and make grander social promises. Calls for a "community" come with the implicit agreement that this codebase now exists for more than just the one person who initialized it. And that you've pushed it into the public, and requested people to treat your repo as the repo, you've taken on certain responsibilities, and made some implicit, or explicit, promises.
Sometimes the job is thrust upon the maintainer accidentally (eg Linus), and sometimes it is requested (apparently in this case?)
But nonetheless it's a natural function of the OSS community, and there are ways to deny the responsibility appropriately, and inappropriately.
But it's there is much more nuance to this than dumping a box, or reading a legal contract (which is never representative of social contracts; it's just the bare minimum to avoid responsibility in the eyes of a lawsuit.)