This is the kind of confusion that could have been avoided by Bostonian using Bob Henderson’s capitalization of God. The author was referring to the almighty creator of Heaven and Earth. Whether you believe in such a concept or not doesn’t matter, what matters is that the link text was intentionally changed by Bostonian confusing the Hacker News reader as to the author’s intended meaning.
If it's "a god" (with article), "god" is a general term, like "chair" in "a chair". If it's just "God" (without article), then "God" is a name, and names are, for some reason, uppercase in English. General terms are almost never upper case, apart from beginnings of sentences, and some confusing exceptions like "American" (country / language adjective). (I'm not a native speaker though)