We didn't rule it out. I worked in an Alzheimer's lab about 15 years ago. In our outside voice for Grant committees, publications, etc. We acknowledged the am

We didn't rule it out. I worked in an Alzheimer's lab about 15 years ago. In our outside voice for Grant committees, publications, etc. We acknowledged the amyloid hypothesis but internally almost every other group meeting the postdocs and grad students disclaimed that we still couldn't rule out "common factor X". It was also morbid humor we would say "oh maybe the amyloid hypothesis is wrong" whenever something strange would come up. We only about 10% joking. It's nice to see that skepticism has finally bubbled up across the field. I like to think we were one of the more honest groups in the field -- I have post-publication corrections on my papers, the lab issued an 11-page retraction (with cautions about what not to do experimentally) when it turned out one of our lab's major findings was an artifact [0]. It's worth noting WHY the amyloid hypothesis sticks around, it's because the prion hypothesis is extremely well supported by the data (even though I think pruisner is a shady dude), so it's not a stretch to think that other amyloid diseases work in a similar way [1]. [0] the grad student who pushed through this paper is a huge scientific hero. [1] there are some subtleties though.