Slightly OT: not exactly anti-vaxxer, but a related "Covid isn't a killer, it's the Deep State taking control" trope.
As a postscript to a childhood friendship which ended several years ago (due to his attempted bullying of my wife), I was copied into a Faceache conversation by a mutual friend about Covid earlier this week, where the ex-friend proudly described the way he was refusing to wear a mask as it was an infringement on his freedom (apparently "maskless" is too negative, "mask free" is his preferred descriptor). "They can't force me so I won't wear a mask, aren't I clever" was the central message, with a big dollop of "stupid sheeple doing what they're told" added for good measure.
My sister works in the NHS in the market town where he and his family lives, and I've heard directly from her the pressure that she and her staff are under in the area. After four pleasant years of no communication with him and complete separation of our families, I lost my rag (both my wife and I had Covid in December, not something I'd wish on anyone, even this conspiraloon) and gave him both barrels on how selfish, wilfully stupid and arrogant he was. It was stupid I know, don't poke the troll etc. I was pretty insulting, and it was the wrong thing to do, but I read his pompous post, saw red, let rip and clicked send.
The sneering response justifying his behaviour I got provided me with two things:
1. Absolute certainty I did the right thing four years ago, cutting ties between my family and his (apart from anything else it reduces the likelihood of us all being murdered in our beds by his trainee serial killer son - dead eyed little freak that he is). My daughter has just read this last bit, and laughed like a drain, saying "It's true!".
2, It brought into sharp relief the lengths some people, regardless of their intelligence, will go to in order to make reality fit into their world view. This guy (who I've known for over forty years) has always been intelligent, opinionated and argumentative; quite how the latter two have overwhelmed the first, I'm at a loss, but apparently he's a conspiraloon of the first order now. But how can someone who for all his faults I always thought was honest and rational come to such a point that he'll believe or promote any old sh1t off the internet because it supports his argument? Of course, the internet turbocharges this sort of deliberate self-delusion; one can always find a Professor Hoozit of the University of Google who supports any contentious viewpoint, regardless of the weight of scientific and medical opinion to the contrary. Another factor is the assumed superiority of the conspiraloon - he knows the Real Truth, everyone else just doesn't understand, or they're lying. You need huge reserves of both arrogance and credulity to make yourself believe that.
Happily, my mate informed me of the Block function on Facebook (who knew?), so I'll never have to read anything from the crazy bellend again. The relief is palpable.