So whats the reason for the revised helmet?

Thats not a new detail its been happening sinceThe Force Awakensfor that character.

Its restrictive in a way.

Star Wars: The Rise of Skywalker

Lucasfilm

So its a physical representation of how that character has grown.

Driver reprises his Kylo Ren role inThe Rise of Skywalker, opening Friday.

Star Wars: The Rise of Skywalker

Lucasfilm