I don't, but I had a member in one of our online communities that insisted on using Medium.

Compared to self-hosted solutions, a medium blog had a professional look from the get-go. This was the major reason why said team member wanted Medium.

I don't think open source projects has yet caught up with Medium editor in it's image uploads, YouTube embedding, or the good looking CSS. Gutenberg and Drupal's Paragraphs has made good attempts though.