I think the title is intentionally ambiguous. Because the article is a rebuttal to those who oppose writing comments (that is where "why not comments" means "w

I think the title is intentionally ambiguous. Because the article is a rebuttal to those who oppose writing comments (that is where "why not comments" means "why you shouldn't write comments") where the main argument is that you should write "why not" comments (that is "why not comments" means write comments explaining why you didn't do something or do something a certain way).