It looks like your question may be about uninstalling WordPress itself, rather than the Automatic YouTube Gallery plugin.
When WordPress is removed, some folders like wp-content may remain because they contain site data such as themes, plugins, and uploads. Many installers leave this folder to prevent accidental data loss.
If your question is specifically about uninstalling our plugin, please note that Automatic YouTube Gallery does not create custom folders in wp-content. The plugin mainly stores its settings using the WordPress Settings API, and these can be removed when the plugin is deleted.
If you meant something else, please let us know a bit more about the issue you are experiencing and we’ll be happy to help.