That said, although both are "broad" they are quite different concepts. The linked "interoperability" cases involve 3 works/parties A, B, and C, and the EFF's claim is that A should have no rights regarding B+C just because B+A existed first. OTOH, the GPL's relevants to linking is that A has rights regarding A+B.
The US definition of "derivative work" is quite broad, and seems to cover linking just fine.
The Berne Convention, however, doesn't mention "derivative works", only specific traditional examples thereof, so it's possible that countries other than the US may have implemented it in such a way that linking doesn't count as a derived work. TODO look up "compilation" (in the copyright sense) and "collective work", which might actually be more relevant for linking?
Edit: "GPL is MAD in the copyright cold war" is a good phrase to describe things.