Helen Hou-Sandi revisits “starter content” which had its beginnings in WordPress 4.7:
“We will want to strike a balance between showing users what they can do and adding too many individual pieces of content that have to be tracked down and removed if they don’t want it…For a future release, we should start exploring what it might look like to opt into importing starter content into EXISTING sites.”
Demo content importers exist for many commercial themes, but outside of a good experience with BuddyBoss (which helps you easily remove the demo content), the demo content is usually hard to configure and harder to remove. I would welcome a stabilization of sorts from WordPress Core for themes.
