At the risk of sounding Clintonian, it depends what "may prevent you" means.
Further in the Fact Sheet, it says:
WHAT ARE THE BENEFITS OF THE MODERNA COVID-19 VACCINE?
In an ongoing clinical trial, the Moderna COVID-19 Vaccine has been shown to prevent COVID-19 following 2 doses given 1 month apart.
So, what does "to prevent" mean?
Clinical trials usually run for years. These shots haven't been evaluated for more than 10 months. If they "prevent" COVID19, let's say, 50% vs placebo today compared to 95% back in December, how does that decay in "prevention" compare to other vaccines at the 10 month point in their clinical trials?
Twitter doesn't have the biostatistical chops to suspend anyone making any claim.
We’ll never know, because tens of thousands in the Pfizer and Moderna control groups began receiving the vaccine.