Actually we aren't "programmed" for long life because it isn't necessary. To be successful, a creature has to remain alive and reasonably fit long enough to produce (and in the case of humans raise) offspring, then it becomes expendable. In fact, our apparent approx. 120 yr limit is already something of an overkill, as most individuals would be long dead before reaching such an age due to accidents and disease.
> This is a common answer, but rather non-transhumanistic. Can't we
> change without having people die? We want our ideas to die instead of
> us.
Yes, what good is progress if you're not around to benefit from it?