"Without data, all you have is an opinion."
Although some studies have concluded that masks help stop the spread of COVID-19, usually they have failed to replicate real-world situations. A common approach is to evaluate the effectiveness of mask material at stopping the expulsion or intake of the aerosols presumed to be the airborne carriers of the virus. Useful information, perhaps, but at this stage, what we need to know is whether the widespread use of masks is measurably reducing the risk of death from the disease. To continue requiring the use of masks makes sense only if there is compelling data that death rates are lower for people who wear masks than it is for people who do not.
We have no way of measuring whether or how much and how appropriately individuals wear masks, but state mandates that people wear them are predicated on the notion that more people will do so if they are threatened with a fine or punishment. Thus, it makes sense to demand that states with mask mandates have lower COVID-19 death rates than states that don't. If states with mask mandates are not experiencing lower rates than states without them, the citizenry should insist that the burdensome policy of requiring masks be abandoned.
Logic or speculation alone cannot provide a reliable answer to the question of mask effectiveness. Neither can the judgments and proclamations of politicians or even public health experts. What we need is data.
The article then goes on to provide that data. Click on the link to read the conclusion.