I honestly wore masks for some jobs in the past, and when it’s hot, back in those saner times, the supervisor reminded us to get out of the dirty zone and get a drink so we wouldn’t get dehydrated from all that sweating in a mask. The mask was used for the really immediate danger that we might inhale dust in large quantities and in some cases, avoid inhaling asbestos. I am not wearing one outside in the heat.
I do the same when the work requires. Real respirators, not a piece of cloth that performs no function beyond signaling virtue or mindless flock behavior