Corded hair dryers don’t need to be taken out of your luggage when going through airport security. The airport scanners are advanced enough to see everything inside of your bag perfectly fine, even if it has a corded hair dryer inside.
Wireless hair dryers powered by lithium batteries will need to be removed and placed in a separate screening bin because the lithium batteries interfere with the screening machines. Any electronic device powered by a lithium battery that’s larger than a cell phone needs to be removed from your bag.