This is a good point, but there's also a key difference.
There's a big difference between "code being in one file" and "code being in one function." It sounds like the OP had something reasonably close to "one function," whereas the HN code has a lot of (what appear to be) small well designed methods.
There's a big difference between "code being in one file" and "code being in one function." It sounds like the OP had something reasonably close to "one function," whereas the HN code has a lot of (what appear to be) small well designed methods.