No doubt these abbatoirs could be improved and putting on the pressure for change is no bad thing. However, I can’t help but feel that a good portion of the outrage comes from people who would be just as outraged even if such a documentary was made about those parts of the beef industry that conform to absolute best practice. What little I have seen of the beef industry in first world countries involves the cattle being treated in quite a robust manner at the best of times. Just ordinary handling of cattle (mustering, branding, drenching etc) is fairly heavy handed. I don’t say that critically: I think it is reasonably unavoidable.
I think if you applied the same tearjerker documentary techniques (giving a beast a specific human name, following it through from birth to death in an abbatoir) there would be almost the same outrage from people who (as the saying goes) like sausages but are best not seeing how they are made, and probably think milk comes from bottles in supermarket fridges.