Essentually it would turn any shortcode on the page into a drag and drop box. Clicking on the box would allow you to edit it's options.
Now with Gutenberg things are very different so this no longer works as it was designed for the TinyMCE editor. Essentially gutenberg does what I had done with this builder so not at all nessisarily now.
But I do plan on revisiting this project in order to create a better Gutenberg block to control shortcodes then the one that exists using some of the concepts and code from this project.