This is simply not true as stated. Further, BioNTech/Pfizer has also show to have reduced efficacy.

The study that all these "simplified" horror-stories in the press are based upon is not giving the full picture.

- The timing cannot show how good the effects possibly are (we know that vector-vaccines take longer to create a sufficient protection) - The sample is tiny - It only talks about mild and semi-severe cases. Nothing in the study about severe cases (there were none in both groups)

AstraZeneca has a huge PR-Problem. Since they were running this in cooperation with research (Oxford), a lot of smaller results were published early, which was taken up by the press out-of-context, simplified further and further when going down the ladder to the boulevard-press.

Further, Germany had at least one politician state ridiculous numbers (8% efficacy above age 65 or 75) since he misunderstood something (only 8% of the participants were in this group) and simply had no idea what he was talking about.

And now it is too late, you can't kill these false-hoods once they circle.

Actually AstraZeneca has some nice properties the mRNA vaccines have not, e.g. etter T-Cell response.