I'd always understood it as the official releases were shifted to pink/magenta because of natural colour fade in the print/negative, and that this became more apparent when the low fade technicolor print pictures (and video clips) from the Senator screening came to light to be able to compare. The PAL 1982 VHS is really pink compared to the NTSC releases from around the same time. I think this was a case of the limitations of the format and the average consumer not looking out for that stuff/expecting as much maybe.