• Gluons interact with gluons, without the need for quarks.

• Many (almost all) bound quark states are not found in nuclei, only uud (protons) and udd (neutrons) are. But there are also all the mesons (e.g. the pion), and a whole lot of other baryons (xis and sigmas and what have you) exist.

To put this into perspective, it feels a bit like calling electromagnetic interaction the »chemical interaction«, because chemistry is explained for the most part by the interaction of electrons. But that would leave out a lot of different ways matter can interact, like Bremsstrahlung, positrons, proton/proton repulsion, and all that.