I saw some references to post-quantum security, but I also saw references to something called "Post-Quantum Wireguard" so it seemed like that was handled by some other project, or at best some sub-component of Rosenpass.
Wireguard has a pre-shared key that can essentially get 'added to' the base key, making it more secure. Rosenpass effectively just makes these PSKs and trades them in a way that makes it quantum secure.
Basically it should be a part of base wireguard, but for now it's a good addition.