How much a place is trusted, which is what a setting’s scope is about.
The distinction is not “was it a file”: a pkl file, a git config or an .npmrc inside a
repository is every bit as much a thing a checkout can carry as hk.toml is. Asking about
files let every custom source — the natural use of Origin::new — walk straight past a
check the spec calls a security property.
So the question is trust, every origin carries an answer, and the default for a kind usage
does not recognize is the least trusting one. A layer that knows better says so with
Origin::trusted_as; a layer that says nothing cannot accidentally be believed.