Pathological troll is pathological.
Bob destroyed his own credibility by suddenly making the rounds of nominally conservative talk shows to scare the pants off of people about mRNA vaccines.
When I was a graduate student, I "tested" four different laboratories in order to select one for my graduate studies. One of those labs was Bob's. In his role as my mentor during that time, he gave me a huge stack of papers to read regarding membrane fusion. He stood me in front of a chalkboard and described the function and biology of the AIDS virus. He had me grow cells and then apply nanolipid particles to them in order to take pictures of the membrane fusion process. When it came time to report my experience in his lab to the new graduate student mentor, Bob told me that I had to incorporate those pictures into a story that tells others how and why cells fuse. In short, he acted like a knowledgeable teacher and mentor, and there was absolutely no indication that he was a kook. When I encountered him at a meeting years later, we chit-chatted and he brought me up-to-date on his research. He also gave me his card and invited me to come visit him and his wife and kids at their farm. Again, there was no indication that he was a kook.
Then, all of a sudden, there he is, spouting out nonsense that he knows perfectly well is not true. And I am left dumbfounded as to why he would suddenly be a charlatan when he never was before.