When I was 15, I became a JW publisher. That was in 1963. I was the only JW in my family, including extended family. My buddies at the KH were going through their rebellious period. I don't think any of them really disbelieved the nonsense, but they did write hilarious notes to one another during the meetings. I remember having Beatles bubble gum cards at the meetings, and one of the girls I sat with wrote funny captions on them. They would also make fun of some of the older people in the congreation and write phony letters from them, highlighting their weaknesses.
All but three of them (myself included) for sure are staunch JW's today. I looked up one of the guys on google, and he is listed as a "religious leader, Jehovah's Witnesses." There were two fleshly sisters in our group, one of whom was responsible for the Beatkes card captions and mocking letters. I found their mom's obituary online, and it was clear that they were still JW's.
Teenagers can't be taken so seriously. The human brain is not fully developed until the mid-20's.
I feel for the kids who have no choice in the matter. They're doing what's expected by others. They have no power but to be mouthy or appear rebellious.