It's actually pretty easy to overstate the amount of harm caused by that one individual... you're doing it.

There are lots of good reasons to believe in the amyloid hypothesis, and no paper or even line of research is the one bedrock of the hypothesis. It was the foundational bedrock of Alzheimer's research back in the early 1990s (essentially, before Alzheimer's became one of the holy grail quests of modern medicine), after all; well before any of the fraudulent research into Alzheimer's was done.

The main good reason not to believe in amyloid is that every drug targeting amyloid plaques has failed to even slow Alzheimer's, even when they do impressive jobs in clearing out plaques--and that is a hell of a good reason to doubt the hypothesis. But no one is going to discover that failure until you have amyloid blockers read out their phase III clinical trial results, and that doesn't really happen until about a decade ago.