I agree that quantum computers offer nothing new beyond a cool exploit of Hilbert space projection. Whether quantum computers offer lots of new computational light or just a handy flashlight for a few dark corners known classical algorithms have missed, they say nothing about quantum mechanics that we haven't known since Bell's inequality was proved in the early 1960s. However, at some point aesthetic considerations in physics move beyond the realm of fashion and become compelling in the minds of most working physicists. QM cannot simultaneously be local , deterministic , and real . Unitary QM rules microsystems between measurements.
Measurements are deterministic, nonlocal events.
Only wavefunctions, not actual particles, behave nonlocally, fortunately. Since relativity can't be formulated nonlocally, let's give up on field theory for now. Measurements are local, nondeterministic events. Same as Everett, except for asking questions with a beginning and ending boundary condition, rather than just a beginning and open time evolution from there. No one anywhere is arguing about the math, only about what it means .