Using the great feature "Accurate User Detection cross devices #3490", there should be a possibility to still know from where/which device which sites have been visited /which actions (events) have been made by the visitor.
Maybe one could give in the visitor profile:
as proposed in the comments from #3490, this was extracted and extended to an extra issue
#3490 is fantastic, but without this visitor profile enhancement it falls just shy of being perfect. I would love to see this come to resolution.