Adding to what others have said, lines of code isn't a great measure of the quality of a project. There's beauty and elegance in simplicity, and creating something well-structured and concise can take incredible skill. In fact, Svelte is also such a project; I believe version 1 was under 2000 LoC

One more thing, software is more than just the code. Documentation is also a critical component of successful and useful software, and the submission does an amazing job of making this approachable and useful through Rich's characteristically clear documentation