Well, it all began in the time of Jenner…and hasn’t truly died out since.
You would’ve seen quite strong covert support for the anti-vaxx movement over the past couple of decades on the Health and Nutrition board with all manner of ideas straight out of the anti vaccine manifesto gussied up as thoughtful decision-making where avoiding the flu, Gardisil, MMR vaccines etc came under discussion as a good idea. And yes, they spilled over to Covid in the early days.
Anyone keeping abreast of developments via TWiV podcasts will have listened to discussions of the development of vaccine hesitancy and suspicion over the years by epidemiologists/virologists such as Peter Hotez (along with the regulars) It’s a sobering indictment of the echo chamber effect of the internet and the general publics’ critical thinking skills.