That shatters one of Joe Biden's main talking points about the Trump admin not focusing on a vaccine. By the time it's readily available for the masses, Biden will be president. Will people be comfortable taking it? Remember, we were told not to trust a vaccine under the Trump admin.
https://www.cnbc.com/2020/11/09/covid-vaccine-pfizer-drug-is-more-than-90percent-effective-in-preventing-infection.html