Already 20 years ago there were serious discussions whether the fibrils were actually responsible, or maybe instead some toxic intermediates might be the cause.

Already 20 years ago there were serious discussions whether the fibrils were actually responsible, or maybe instead some toxic intermediates might be the cause. As far as I understand the case against fibrils as the main cause only got stronger, and the mainstream view among scientists is that it is quite likely that there is more going on there and the fibrils alone are not the full explanation.