Do you believe that if a vaccinated individual can still get COVID that means that the vaccine doesn't "work" and nobody should get it?
Define vaccine.
A flu shot protects against specific strains of the flu. If a variant spreads the flu shot is ineffective. The flu has not been eliminated.
If you feel the vaccine protects you than you shouldn’t be concerned with others carrying the virus. But it appears you know the vaccine doesn’t offer the protection you thought it did, so now you think others not being protected are the key to your safety.
Covid is here to stay. Boost up because it is going to be a long ride.