Interesting to hear that compliance in Thailand is close to 100%, whereas here in Cambodia 50% estimated. Recently I attended an event for foreigners in Kampot and of about 50 participants, nobody was wearing a mask (neither did I, I only carry one to put on when required or in crowds).

In travels in Vietnam I counted 99% of mocy drivers were wearing helmets, long way to go for Thailand.

From my time in the army, or was it from reports going back decades?, there were stories of partially un-screwing the filter for gas masks to allow air to pass on the side. A filter for a gas mask is indeed a noticeable resistance to air flow. There might be ways to tweak a face mask to look like it's properly working, but allowing all air to flow in and out unfiltered?