Bob Dylan was too fucked up by amphetamines and the motorcycle accident, that's why his voice changed and he was reclusive: most accepted hypothesis
Bob Dylan died in the motorcycle accident and was replaced by someone else, so they needed time to cover up it and to make it acceptable for him to look/sound different: not so accepted but still an interesting hypothesis
Bob Dylan started taking testosterone circa 1966 and needed to stay away from the spotlight so people wouldnt start noticing it: Best hypothesis. Not accepted between people who dont want to see the truth.










