The real reason is the drive traffic to their site. You must be new to this. Apparently this is "the" way to drive traffic / growth now, i.e. by writing these sort of short blog posts now. It's the "growth hacking" way. I have a product in the Chinese market so I haven't really used these kinds of marketing techniques. Maybe someone else can chip in how well these methods work in driving traffic and subsequently conversions, I'm genuinely curious as well

Don’t let that slow you down. Just launch the damn blog post and let your readers tell you what you should hope to accomplish.

They get the author's company/brand on the front-page of HN, for a little name recognition.

It's an ad.

Indeed, this was a creative, even literary, entry but it makes a memorable case for overcoming writers block, I mean, entrepreneur’s block.