A few things we know about vaccines and masks.
1. The vaccines work over a time span of months at a maximum level of 70-95% effectiveness in preventing disease.
2. The vaccines have been decreasingly effective over time, possibly falling below 50% or less after 4-8 months if you believe Israeli studies. It's unclear whether this is because they can't cope with new virus variants that arise, or simply that the immune system response to all variants declines over time.
3. Anecdotally (based largely on CDC data from a Provincetown, Massachusetts outbreak among vaccinated people), even vaccinated people will carry a sufficient viral load (after exposure to the delta variant) to be infectious to others.
4. There is conflicting information as to the utility of booster shots. The White House and CDC are recommending immediate implementation of boosters, but this is over the objections of scientists at the FDA - two of whom (a director and deputy director) resigned over the WH's politicization of its booster program. The European Union is not, at this time, recommending a program of booster shots. There is a social justice angle to opposition to a booster program in wealthy countries while billions of people in poor countries have not had access to vaccines at all. With respect to booster shots it's not clear any one on either side is following the science.
5. Israeli studies strongly show that natural immunity obtained by contracting the disease provides protection from infection that is far greater over time than the protection provided by the best vaccine. There is no gain to vaccinating people who have once been infected by the virus. This poses ethical obstacles to vaccine mandates that include those already infected by Covid, and especially to requirements for universal vaccine passports.
6. Studies on masks are in conflict, but a recent, apparently authoritative, study in Bangladesh showed a 5% reduction in disease among people wearing cloth masks, and and 11% reduction among people wearing N95 grade masks, both as compared with unmasked people (with, however, very broad confidence intervals about those numbers).
7. It's unclear whether or not mask wearing promotes riskier social behavior sufficient to offset the benefits of wearing the mask.