I think McCarthy and Ewers will both stick around for one more year. Right now on paper their is going to be a brown horde at the QB position for the 2024 draft much like the brown hordes crossing our borders unchecked.
They both are very good QBs but getting an extra year of his experience and playing time in college isn't the worst thing in the world. Both are only in their second full year of being starting QBs.
Maye should absolutely declare though, he's an elite QB already. Nix has a big game coming up and it has both draft and Heisman implications so I am rooting for him as well.