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Of course, I agree. The problem is that even in textbooks often "photons" are used in hand-waving arguments, particularly in GR textbooks, where what is in fact meant is the eikonal approximation of Maxwell's equations in "curved spacetime". Of course that's a tremendous shortcut in calculations.
What's always wrong with this "naive photon picture" is the assumption that "photons" were localized massless particles. So if you envoke the "naive photon picture" you are always better off when thinking in terms of em. waves than in terms of massless point particles.
Field quantization, is of course, not only needed when you deal with Fock states. E.g., you need it also for thermal radiation. It's not by chance that the entire discovery of quantum theory historically came from Planck's discovery how to theoretically describe thermal (black-body) radiation!
What's always wrong with this "naive photon picture" is the assumption that "photons" were localized massless particles. So if you envoke the "naive photon picture" you are always better off when thinking in terms of em. waves than in terms of massless point particles.
Field quantization, is of course, not only needed when you deal with Fock states. E.g., you need it also for thermal radiation. It's not by chance that the entire discovery of quantum theory historically came from Planck's discovery how to theoretically describe thermal (black-body) radiation!