The masks they peddle in stores are labeled as "not for medical use". I mean, damn! They have holes in them that I can see through with my bare eyes!
Masks that are protective, are called respirators and are part of a class of equipment called PPE (Personal Protective Equipment). The word "Personal" is in the name, because it is designed to protect the wearer, not those around the wearer, and is limited by the rating (P100 being the rating that will actually reduce the risk of some viral infections a reasonable amount, while N95 is for larger particulates like airborne dust and pollen). Will they (including those rated for dust) help reduce the risk of spread from the wearer to others around her/him? Of course, but only as long as the virus didn't go airborne and, even then, "only" up to 20% reduction in risk. Airborne viruses, like the coronavirus family of viruses, are able to penetrate the fibers and travel, but the layers of the respirators and non-medical masks slow that travel considerably.
I don't think that people should be required to wear masks. If you want to wear one, please do so and protect yourself with your PPE. If you'll see me around, I'll be wearing mine. But if you don't want to wear it, I believe that that's your freedom over your own body. It's your choice not to wear one, just as it is my choice to wear one. If someone makes fun of you for wearing a mask, I believe it to be your freedom to punch them in their throats.
The issue, as far as I've noticed, is that people think they know something, when none of us really do. Even our scientists are waffling back and forth on the subject. We all do what we feel is best for us and ours, and we should allow others to do the same to them and their.
Additionally, if someone around you is terrified, and would prefer you wear a mask, I think you should wear a mask (or not be around them). As I've said, we're flying blind, and, sometimes, we need to feel safe whether or not we really are. Just be a good human.
Lastly, up to 20% reduction in risk of spread isn't anything to sneeze at, after all (pun intended). Do the right thing, whatever you feel that is, and respect others as they do their right thing.
[E] You don't have to agree with me, but it is scientifically accurate. I hope you don't disagree with the "be a good human" part, though, since... why would you not be a good human?