It really is true. I won't pretend all anti vaccine mandate people are the same, and it should be noted that those against the covid mandate are probably mostly for all the other currently required vaccines, but these so called anti Vaxxers come in 2 varieties. The most common variety is type 1.
1. Believes that vaccines should not be mandated. Many of these people are vaccinated
2. Believes the vaccine is dangerous and people should be warned
It ia possible to have some overlap in those groups as well, but there isn't much overlap.
I can see type 2 believing everyone is sheep, but type 1, most likely doesn't. It seems like you are just assuming their internal thoughts based on stereotyping antivaxxers. It used to be that we stereotyped people based on gender or skin color or religion. Now days this has been mostly replaced by stereotyping a wide range of people who share a similar opinion on a subject, with the opinion arrived at through a wide variety of opinions.