Is Kang's hair a wig or a bald cap?

Even your hired gun, Lawyer Kang, openly exposed that it's a cap.
Hair loss is genetic, so how disgusting is it to mock someone for it..
No one mocks Lee Jae-myung by calling him a cripple for his golf-playing arm..
The funny thing is, does being progressive mean you don't lose your hair? lol
https://youtube.com/shorts/ljIkg9hYtKE?si=zA2Uz1vzYcRCVsu5