It does not matter if the config process uses pkgconfig or not.
Depending on the package name is not a way to state you're not using
pkgconfig, it's a way to get broken builds when the package you depend
on gets restructured.
Then the docs should be strengthened to state the case from the perspective of the
providerof the .pc and not the consumer of it:
Current:
"Fedora packages which use pkg-config to build against a library (e.g. 'foo')
on which they depend, SHOULD express their build dependency correctly as
pkgconfig(foo)."
becomes:
"Build dependencies on Fedora packages which provide pkg-config files SHOULD be
expressed as pkgconfig(foo) and not foo-devel, whether the dependent package uses
pkg-config or not."