No way man, if I was immortal, I could work on stuff without worrying that I'll get old and never finish it. And there's plenty to work on, for sure...
And you still can, even after this "immortality tech" is available. Nobody forces you, just don't hold the rest of us back when it's time to join the revolution ;-)
Seriously though, you guys are going to die out. You know that, right?
When there is a price on immortality, we will all die or be killed.
Humanity is notoriously self levelling.
I would be very surprised if the part of the brain responsible for motivation was so directly tied in with the part of the brain which is consciously aware that it will die.