Well, potentially, a mask breeds microbes in its warm, damp fibers and potentially gives you pneumonia. So, yes, it does something.

If it does not protect the eyes...it is useless. If it cannot stop the flow of aerosols (and it doesn't), it is useless. All this nonsense about constructing a safe bubble around yourself is useless. Better to keep your vitamin C and D levels up, take zinc supplements, and have access to hydroxychloroquine.

You think there is a "science" about the masks? Then what is the performance metric? What number does it have and what does that number correlate with regarding risk of infection? You are not going to find it. The studies I have read end up as a push: maybe it works, maybe it doesn't. That's not science. That's wishful thinking.