"Common Sense" regarding an mRNA vaccine? "Common Sense" would tell you that a combination of chlorine and sodium would be poisonous and that a combination of hydrogen and oxygen would be an explosive gas.
Masks absolutely work, or maybe tell your surgeon not to bother wearing his or hers so they can exhale some pathogens directly into your abdominal cavity. I assume that you're playing your favored role of ignorant troll, but no one promised that masks are 100% effective, nothing is, and different masks have different purposes. Surgical masks don't prevent you from breathing pathogens in, but they do keep breath droplets and sputum from going into others' eyes and lungs. But fuck everyone else, right? That's what America stands for to people like you.