It gets abandoned but unlike closed software, if you depend on it enough, you can continue using it forever. For some reason if GitHub says ‘updated 6 years ago’ it is not viable for people, but for many things, especially desktop apps, this doesn’t matter at all; it works fine and if you need updates, you can do them.

The point is you can, while with closed software, you maybe can and sometimes with a lot of trouble.

If the source is open, the file format is also open.