Hey you! Yes, you! Thank you for adding beauty to the world!
Definitions of walled garden:
noun: A garden enclosed by walls for purposes of shelter or decoration.
noun: (figuratively, media, technology) A closed platform for content or services controlled by a single carrier or service provider, typically requiring subscription to access.
noun: (Internet) A set of webpages or other resources that are richly interlinked and share a common focus, but have little or no linkage to or from the larger network.