Paul Scanlon shares his journey of developing the MDX Embed plugin as part of his 100 Days of Gatsby challenge, which allows users to embed various media content like Twitter, YouTube, and Instagram into MDX files without imports. The plugin aims to improve performance by using the Intersection Observer API to load content only when needed, in contrast to the traditional method of loading everything upfront. Initially developed for Gatsby, MDX Embed has evolved into a universal tool that can work with any MDX environment, a shift marked by its transition to a new monorepo and website. Despite facing challenges such as low initial interest and the need for a better repository structure, Scanlon highlights the support he received from the community and his excitement over its adoption by prominent figures in the MDX community. He encourages contributions for testing to reach a stable release and hopes that major blogging platforms will eventually adopt MDX Embed to enhance their performance.