That's not true, you both have the same view of the world. *Unless you play locked camera*. In that case blue sees more of the interesting part of the world than purple during laning phase (i.e. the region of lane in front of you). Unfortunately the game is not optimized for locked camera.
I mean, you agree that this is an issue for people with locked cameras, but you don't want the solution to effect people who don't use locked camera.
So; offset the camera lock? Make the purple camera lock slightly farther ahead. Or, for that matter, let people adjust where their camera locks. They can lock it wherever they'd like to.
Problem solved, and it won't impact anyone who doesn't use locked camera.
One other thing though, you mentioned previously that the game is not optimized for locked camera play. So, why is locked camera the default mode? If you don't intend for people to play in locked camera mode, it shouldn't be default.
(note, if I'm wrong about locked being default, nvm. I haven't used locked camera since I first started playing, but I think I remember it being default)