It is common knowledge that the amyloid hypothesis only holds water for about 1% of all Alzheimer's disease (AD) patients. Those folks inherit genetic susceptibility factors that cause higher amyloid production or slower amyloid clearance, and they develop AD earlier than sporadic cases. We still routinely use those amyloid-heavy genetic mouse models of Alzheimer's in the lab to test memory effects of different drugs or interventions, so there's still a heavy amyloid basis in research even though it may not apply to most AD cases.