[jjulius]

Manufacturers, CDC, etc. were explicitly clear about the difference between preventing infection and preventing severe illness upfront. If you heard, "How can you be so cruel? Take it for grandma," and went along with it thinking that that meant transmission is prevented, then you received that "message" from someone who - for lack of a better phrase here - was not an "official" messenger and/or was speaking out of ignorance, and you then opted to read no further into the accuracy of that statement yourself.