>>105907048 (OP)They cool the chassis, the chassis isn’t actually as big of a factor in total system cooling as people think. The heatsink isn’t directly connected to the shell/chassis of the laptop, it’s just radiant heat that makes it feel hot, and cooling that just makes the shell cooler, doesn’t actually make the system cooler.
Unless you have a heavily vented bottom chassis, in which case yes, throwing a fuck load of airflow at the board will help. But if your laptop just has some sliver vents on the bottom it won’t do anything.
If you have an ARM MacBook Air then these also help because they do use the chassis as a heatsink.