There is a tremendous amount of disagreement about the value of facemasks. The CDC recommends them and I see it as a "why not?" sort of situation. However, how effective they are against Covid is absolutely an open question.
They're being recommended for everyone because we don't have the testing capacity to know who is or is not positive, or who among the positive are asymptomatic. Otherwise, a healthy person wearing a mask is a waste of that mask and can absolutely lead to a higher risk of infection since people seem to think the mask makes them impervious to infection.