What is the precious metal content of e-waste verses raw ore?
Depends on the plating/solder/components used. High stress environments use silver/gold, but most e-wast is likely Tin and Nickel for solder with copper traces none of that is the bad stuff. The reason the processing is so regulated is that to strip it all down quickly and economically they have to use some very harsh stuff - that is where the real hazard is....that is the main issue and then the plastics in the insulators between circuit board layers and chips.
It could all be dealt with but the enviro-weenies demand their power and the industry is too small profit wise to be able to push back much.