[exolymph]

What drives Twitter threads is that there are a bunch of readers on Twitter, and it's easier to reach them there, where they already hang out, than to get them to visit a blog or whatever offsite. This is exacerbated by Twitter itself downranking links and upranking threads, because Twitter doesn't want people to be directed offsite. Unless you have strong incentives to care about getting your readers offsite (e.g. to get them on an email list so you can reach them more reliably in the future so you can sell them something), it's more efficient to just blog directly on Twitter.