The initial vaccine did stop infection and prevent transmission remarkably well for a window of a few months after taking them.

Not saying so would have been lying.

More cautionary statements than were given could have been given about the speed at which the immune response might dwindle, and how the virus might evolve, but those were in evidence too if you had more than a couple of minutes of attention span.

"You were right but didn't hedge hard enough!" is hardly the same as "being a big lie".