Although the COVID pandemic is apparently winding down, it is still a very smart thing to wear a mask in Bangkok.
Using the APP IR Air Visual Quality, there are a multitude of days and evenings throughout the year where the air quality of Bangkok is extremely poor to the point of getting sick.
Exposing yourself to all these toxins day in and day out is only going to worsen your health now and in the longer term.
Checking the air quality before going out in the city and wearing a mask is the only smart thing to do.
Be Mask Smart!