There are signs that Gutenberg is being considered…
There are signs that Gutenberg is being considered for adoption on some level in Drupal. There is already a demo of Gutenberg in Drupal, and there is a talk dedicated to the subject at the upcoming Drupal Europe conference.
Yoast recently showed off its Gutenberg SEO Sidebar, which is included in the recently released Yoast SEO 8.0 plugin. The plugin will have two meta boxes: one below your post and one in the sidebar.
Matt Watson has launched Secure Blocks. It allows other blocks to be placed within a secure block and shown, hidden, or replaced with alternative content based on whether a visitor is logged in or not, or by their user role if they are logged in. Additional types of secure blocks are planned for future releases.