@timburkart: For now you can use shortcodes to use Essential Content Types in the Gutenberg Editor. You can check out this article to know more about using shortcodes for essential content types.
As Gutenberg itself is in its beta version which is meant for testing and not meant for using in live sites the plugin doesnot support it and you will need to use shortcodes for using the plugin.

Let me know if this helps you out!
Kind Regards,