> How does it fail to meet this criteria?
Simple: when you choose not to extend your life, you choose to die. When
you are dead, you are unable to pursue your own interests (barring
afterlife presumptions). Therefore, when you choose to die, you choose to
contradict the rest of your value system, if your life has any use at all
in bringing about that which you value.
Since I doubt that Hayflick would like it if I offered to kill him, we may
presume that he values his own life or that his life is extrinsically
useful in bringing about that which he DOES value. Whichever it is, if
immortality is possible then he necessarily contradicts his own value
system by refusing it.
This may not be true if for some reason his life ceased to be
extrinsically useful in bringing about what he valued. However, it is
probably false to presume that it never could given lots of time. So even
this case is not sufficiently strong to endorse suicide.