Much of the confusion around masks stems from the conflation of two very different functions of masks - ingress and egress.
Masks can be worn to protect the wearer from getting infected or masks can be worn to protect others from being infected by the wearer. Protecting the wearer is difficult: It requires medical-grade respirator masks, a proper fit, and careful putting on and taking off. Unfortunately this is probably what a majority of the public believe is why they should wear a mask. But masks can also be worn to prevent transmission to others, and this is their most important use for society. If we lower the likelihood of one person’s infecting another, the impact is exponential, so even a small reduction in those odds results in a huge decrease in deaths. Luckily, blocking transmission outward at the source is much easier. It can be accomplished with something as simple as a cloth mask.
Remember, new infections start from people who are already infected and mask wearing can help prevent them spreading the disease.