Technically those with miniLED can, at least Apple says so. The Airs cannot as they have display tech that cannot heat up much in the first place. My Macbook even with set to 1000 nits for hours in summer does not turn brightness down at a point where the bottom part of the display gets so hot you can't touch the back of it for more than a second. And that's with a third party tool enabling those 1000 nits, it's not even default behaviour.Do Macs reduce the brightness when running hot?