[MatteoFrigo]

You cannot conclude anything about the 16x difference (TFA says 13x, by the way) from the number of dead patients.

As a made up example to illustrate this point, assume that people are either "lucky" or "unlucky". Unlucky people die when they get the virus. Lucky people never die. Assume that one person per million is unlucky, and assume that the vaccine does absolutely nothing. Then this experiment on one million people would find one death in the vaccinated and zero deaths in the control group, inferring that natural immunity is infinitely better.