And 19 out of 20 people will not understand the difference between that and one of those blue cloth masks a dentist wears.

Because they are conditioned to alway look for one common denominator, the lowest one at that, meaning their thought-process is something like this:

Mask stop virus Dentist cloth mask is mask Therefore cloth mask stop virus

I can't really say how much I do value and appreciate what you and many others are doing, but you are severly overestimating the intelligence of the average person - the mass instinct and the "follow the leader"-impulse is stronger than any capacity for thought, and no education can trump that.