When someone wants to create a plugin and is using the Matomo version from matomo.zip, they probably get an error like this one:

Uncaught exception: Error: Class 'Piwik\Plugins\ExamplePlugin\ExamplePlugin' not found

This is expected as Matomo doesn't ship with the Example* plugins anymore, but doesn't help the person struggling with this.

Instead, the generate:plugin should detect if those plugins are missing and if not point people towards https://developer.matomo.org/guides/getting-started-part-1