Code ‘samples’ will misrepresent you

"My personal recommedation is to have a nicely populated GitHub profile and send the link to that. If asked to narrow it down, pick a project that you’re proud of and submit it in its entirety."

Great if you work mostly on open source projects. My clients would not be happy with me publishing their code on GitHub or sending it out in its entirety. I can usually get permission to show snippets or maybe one source file, but most companies view their source code as valuable intellectual property. That's why they ask you to sign an NDA to see it.

To expand on the journalist angle, eliminating candidates who don't have a "well populated GitHub profile" is like eliminating writers who don't have a body of work published in The New Yorker.