The Perfect Blog Post Length

Last week I came across this online article, Study: The perfect blog post length—and how long it should take to write, on PR Daily and the title immediately caught my attention.
Before I get started with my blog post, what do you think is the perfect blog post length? 500 words? 750 words? 1000 words?
According to this article the perfect blog post length is 1,000 words and should take 3 hours and 16 minutes to write.
Now as a public relations professional, I personally think 1,000 words is way too long (who has the attention span to write, let alone read, a 1,000 word blog post?) and if we each had an extra three hours and 16 minutes to write a blog post every day then we might be unemployed. I say this somewhat jokingly but since HMA Public Relations blogs every day and was recently ranked 50 in Feedspot’s Top 100 PR Blogs for Public Relations and Marketing Communications Pros, I think that we do a few things right.
On average I think we each spend about an hour researching, writing and editing our blog posts. In addition, it appears the average length of our blog posts are around 500 words each. We usually have high readership to our blogs, and I think this is attributed to the fact that we not only have good content and information related to public relations and marketing but we also take the time to share our blog posts across our social media platforms.
Now I would like to hear from you, in your opinion what is the perfect blog post length and how long should it take to write?