The n95's protect the wearer, not everyone else. It's like an air filter, it stops dirt from going in the engine. The problem is if you try to wear an n95 in a hospital as a patient, you aren't allowed. My wife's coworker was told he had to change his n95 to something else. An n95 has an exhale flap and anything you breath out just dumps to atmosphere.
If everyone had an n95 we would be fine but that's not possible. All other type of masks are just trying to trap the big chunks out of the air if you cough, sneeze, or talk moistly (hehe, moist).
The best analogy I have seen relates wearable masks to splatter screens. It reduces the big spit chunks from going into suspension in the air or on surfaces. Beyond that if you cough, you still have a unit of air leaving your lungs at a flow rate which greatly exceeds anything that something the size of your face can flow so the small vapor suspended virus particles are still going out.
All the experiments that show beneficial results from mask wearing I have seen are (in my view, but I havn't gone searching thoroughly lately for new stuff) run by people who don't understand the concept of a control volume. They have people sneeze at plates held in front of them at varying distances with or without something infront of them and say hey, when you wear a mask it stops the particles from going straight out. I totally agree, but there is still a volume of air going out between your face and the mask that is going into the air. Does the mask divert that flow in a disk shape around your face instead of just a cone from your mouth? Nobody seems to test that.
I sat in a conference call for work where some professors at the university were trying to determine how to hold in person labs. They were discussing putting those clear plastic barriers up in between students. The main airflow research guy said they are pretty much worthless and it's like putting up a barrier in a restaurant where on one side they have a smoking section and the other side it's non smoking. The smoke smell still drifted to the non smoking section. Basically when you go to a grocery store and they have those barriers up, they are worthless. I guess if you had someone sneeze at you without a mask they might do something, but if you have a mask mandate, it's pointless.
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