That's inconsistent messaging from Corsair, then. Parent comment quotes the times they're like "ehh, they're same thing, don't worry about it" and then they go on to say "well TECHNICALLY there's a teeensy difference in conductor sizes"???

Either they are confident that the 0.25mm terminal difference is within tolerance enough that they consider 12VHPWR to be functionally equivalent to 12V-2x6, or they're getting themselves confused let alone the target audience of their article.