More than anything it would have affected Jon's motivation and inspiration to create new music.

Imagine being able to sing like he did in the 80s and 90s. What a gift!
Obviously you want to share that with the world, you want to write rocking songs, and you want to go out there every night and wow the crowd.

And then you have that gift taken away from you! You not only lose your vocal range, you also lose your tone, and you cannot even pronounce words properly anymore. Obviously when you lose your ability you don't feel like rocking.