Failing to create a plugin-project when following the tutorial.

I am trying to write a SOAP-UI plugin. I am following this tutorial:

https://support.smartbear.com/readyapi/docs/configure/plugins/dev/develop/project/install.html

When I issue the described command 

mvn org.apache.maven.plugins:maven-archetype-plugin:2.4:generate -DarchetypeGroupId=com.smartbear -DarchetypeArtifactId=ready-api-plugin-archetype -DarchetypeCatalog=http://smartbearsoftware.com/repository/maven2/

then I am asked for groupId, artifactId, version and package but not more and when I click 'Y' at the end to accept the settings it creates a barebone HelloWorld example.

This is not what I expected! According to the description I should also be asked for language and type. At the latter I would want to specify Plugin (as suggested by this reference in the description: ReadyAPI Plugin Archetype) which should create an example plugin project as described here: https://www.soapui.org/extension-plugins/developing-plugins/plugin-development/#1-3-2-Create-a-Basic-Plugin-project (or at least something similar).

Why am I not asked for the type of project to create? What am I missing? How does one actually create a Plugin Project skeleton?