Microcontent is a real term with a long history in information design. It originally meant headlines, summaries, and labels, the small pieces of text that carry disproportionate weight. It now also covers short-form posts, clips, cards, and the whole atomised content economy.
That range is useful. The name fits a content platform, a publishing tool, a UX writing resource, a creator product, or a research organisation studying attention and format. The UX writing reading is worth flagging: microcopy is a recognised specialism with a professional community and no obvious central resource.
On the .org, the education, research, and community readings come forward, which suits a professional body, a standards resource, or a publication rather than a product.
One compound word, twelve letters, no hyphen, phonetic, and the micro- prefix is permanent vocabulary. It describes a structural feature of how information is consumed rather than a passing format.
Enquiries welcome.