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Please look up the size of individual H2O molecules (which are what you exhale, not water drops).

It isn't the water molecules passing through the mask from your mouth. Your body is warmer than the air around you most of the year (unless you live in the tropics). It is mostly the heat of your breath passing through the mask, then hitting the cooler surface of the glasses, and making the moisture in the air that is already outside your mask condense on the glasses.

Water particles aren't getting through. Please look up how condensation works, it's about a difference in temperatures.

Water particles absolutely are getting through. Yes the glasses are colder and breathe is warmer but it is still the water vapor from the hot moist breath that is the primary source of the water condensate.

While water particles do pass easily, viruses may not as respiratory aerosols are orders of magnitude larger about 1.6-5um vs. water at 0.27nm