Thai people will decide when they will stop wearing masks, not you or 'Thai officials'.
Many people in Thailand wear masks for a variety of reasons, irrespective of those highly informative, so-called intelligent westerners who Poo-poo Thai people for wearing them.
Their reasons include: allergies, (of which my wife suffers from), traffic pollution, the current problem of polluted air due to crop stubble burning, protecting themselves and others from colds, flu, etc., or even 'B.O'. (foreigners and bad breath.
Leave them alone - they're doing you no harm.
Or do you feel guilty............