RFK Jr's voice has nothing to do with age, it's a medical condition. Scott Adams, the Dilbert guy, had the same and had a surgery that fixed it. no idea why RFK Jr hasn't had it.
RFK Jr was game to continue the interview but as is typical for the incompetent Noory he mangled the end of the hour and bum rushed a stunned and insulted RFK Jr out the door 'ok goodbye Robert'. To make way for 2 hours with another crackpot Coast tard faking he's a physicist.
Noory lost his voice at one point, happening more often, the long goodbye is underway.