This all relies, as the article points out, on everyone looking directly at code that both looks like and works like the only extant codebase for EXT4 and nonetheless concluding that in fact the computer conjured it from the aether. If I wrote a program that zipped up the Linux kernel source, unzipped it, and grepped -v for comments it would not then be magically transformed into unattributable public domain software.

Under the premise advanced in the quote, copyright is not being violated because there is none. Thus, the quote makes no sense as stated. It may be that, additionally, copyright is in fact being violated (I don't believe it myself), but if so that's a separate argument.