It's the audience. That's where the audience is.

Also Twitter is amazing, you always see stuff only from the people you follow, so he knows his audience is people who want to listen to him.

Let's put that another way, then:

Why use Twitter for the whole post, rather than using it for a summary or above-the-fold section of the post, with the actual post hosted somewhere else and linked to from that summary tweet?

It's not as if any of the individual tweets, other than the first one, were formatted usefully as soundbites worth an individual retweet. The only thing people were sharing/responding to was the first tweet. So, AFAICT, that's the only part that needed to be a tweet, right?

Clicks through drop off really fast. I know I almost never do it. The tweet thread format is good for information in small bites. I know that each tweet has got to have more information and I can just stop at the first that is meh because it's written for insiders.

Articles on the other hand are written for an audience that usually likes more background etc. because that audience will complain if the background is absent.

But you have to click the tweet to see the thread anyway. What's the difference between clicking through to the thread, and clicking through to open the article in the embedded webview? Either way, you're stuck synchronously looking at the story until you click "Back."

If it's just a matter of journalistic style, I assume there are people out there who write articles the same content-dense way people write tweetstorms; you could just decide to only follow such people.

I don't know what to tell you except that tweets are way more information-dense than anything else. The Medium audience demands "modern long-form" style with personal anecdotes and all that. The Twitter audience demands the punchy short stuff. So I know what I'm going to get on Twitter.

To be clear, I’m not suggesting someone write for some other audience or site first and then share the results on Twitter. I’m suggesting that someone write for Twitter, starting off by writing essentially the tweets they were going to write, but offline in a text editor; then edit the resulting paragraphs for readability/flow; then slap that prose into a Gist and take the https://gist.io/ view of it (or do any other equivalent "pastebin to clean, unlisted-but-linkable HTML page" flow); and then publish the first of those tweets, as a link to that HTML page.

In other words: maintain a blog on Twitter, where the tweets serve as the blog’s chronological index / human-readable RSS-feed and interactive comments section; and floating text pages hosted in arbitrary other places serve as the blog’s content. This idea is what “microblogging” was supposed to mean, before the media re-interpreted it as being equivalent to “really enjoying this poop I’m taking”-style life-logging.

I’ve always been surprised that Twitter itself doesn’t have a built-in first-party workflow for this. Tumblr, the other 20-year-old microblogging platform, does: you can publish a post with an embedded “Read More” break, that will hide everything below it in your feed but show it when the static-HTML version of the page is viewed, with the “Read More” link at the bottom of the post in the feed, linked to said static-HTML page. It would make a ton of sense to me for Twitter to have something that’s half this, and half Reddit’s approach to text posts: giving you the ability to create a tweet that, instead of having a linked URL to go with the tweet, has a longform text body to go with the tweet.

Think about the fact that you can “attach” a multi-minute-long video to a tweet as a first-party workflow, and Twitter will host the video for you — but you can’t “attach” a multi-minute-long blob of rich prose text, where Twitter will host the text for you. Seems silly when I say it that way, doesn’t it?

Haha, I get what you mean, but the people who want that get that from the Thread Unroller apps so the need really isn't there. The Twitter restriction ensures that I get Tweet-style content.

They're going where the audience is, and where they can get maximum exposure (retweets).