Who actually ran HL1 at 1600x1200 or 1024x768 in 1998 unless they had a high-end PC? The minimum requirements basically expect 320x240.

As an aside, I'm really, really tired of people quoting the larger number after the smaller number for landscape resolutions. X goes BEFORE Y, damn it! I know this is the publication's fault, because they did the same thing in a different article.