Trivia: The kick Devin uses to win her match in the montage is the same one Johnny used in the tournament montage from The Karate Kid (1984).
Trivia: The chop to the back of the neck Dimitri uses in the montage is the same move Daniel used to win his first match in The Karate Kid (1984).
Answer: Just like in the original film, some guys want that brutality. Johnny in part opens the dojo because of his past rivalry with Daniel and to train a kid that's being bullied. But also, other kids that are being bullied want to join in order to learn to fight back. Johnny is also teaching the Cobra Kai creed (Strike First. Strike hard. No Mercy.") so that's why he opens his dojo with that name and the old Cobra Kai dojo's past reputation is exactly what he wants to elicit.
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