That article is about SARS, not SARS-CoV-2. And it does not answer where anti-vax conspiracies originate or why people are so prone to falling for them.
Yes, some antibodies can lead to disease exacerbation rather than protection. This is why there are not vaccines for some truly terrible diseases. This is why, once you have survived dengue fever, you do NOT want to catch dengue again because the second infection can kill you. Specifically, it is because of the problems with the SARS vaccine efforts that I tried to warn people months ago not to count on vaccine development efforts being successful against SARS-CoV-2. We are lucky in that the problems seen with SARS vaccine efforts did not duplicate themselves during SARS-CoV-2 vaccine development.
In any case, anti-vax kookery originated long before any of us were even alive. I’m just curious about its appeal.