the tricky bit with this is that it may be, in a certain narrow context, true.

once you have a case, having been vaxxed may make it less severe. the evidence that it at least used to do so with ~50% reductions looked sound. whether and to what extent this is still true under omi is not clear. it looks like it has faded to me, but i'm not sure.

but this is not the whole equation. if you have 4X the case risk, even a 50% reduction in severe case outcomes still yields twice as many.

much of what is being called "vaxx efficacy" is ignoring that and engaging in bayesian datacrime especially as it's taking the overall higher rates of spread as exogenous and not a function of vaccines.