Correct me if I'm wrong... I thought the same thing about the gaiter since it would be an easier thing for a lot of people to wear, BUT it's not as effective as other mask-types for infection prevention due to the way particles spread.
My read of the study was that the gaiter-type mask will disperse infectious particles even more than a non-mask wearer because of the gaiter fabric creating smaller particles that will travel farther and linger in the air longer than larger particles that will travel shorter distances and fall due to their weight.
Decent image rendering I found that illustrates the concept: