The flaw itself is absurd but then just accepting it as "by design" makes it even worse.
Conceptually, I agree it should be easy, but I suspect they're stuck with legacy code and behaviors that rely on the current system. Not breaking anything else while fixing this is likely the time consuming part.
if (metadata.is_public)
Simple fix.They can easily withold information they put out intenionally.
If you can't easily architect around it, then don't do what you're trying to do.
"Oh I needed to disclose user data in order to make more money" isn't an acceptable excuse.