Why is this on Hacker News? Just seems to be an ad. If they had written a blog or an article explaining the resons behind this, it would be different. But this

Why is this on Hacker News? Just seems to be an ad. If they had written a blog or an article explaining the resons behind this, it would be different. But this adds no value to HN. Would this have been acceptable if it had been a link to a site other than dropbox?