This question/answer is the standard fallacious response to anybody talking against the anti-aging current.
Some people may indeed prefer to die, some people may be religious or whatever, but most people doing the criticism just give extremely low prior probability to not dying due to some technological/medical advance (during their lifetimes at least), so they consider obsessing with something that is virtually impossible for the hope that it will happen a waste of time, of the finite life they have.
Then it boils down just to whether one is curious about it, or is curious about any other X subject.
Some people may indeed prefer to die, some people may be religious or whatever, but most people doing the criticism just give extremely low prior probability to not dying due to some technological/medical advance (during their lifetimes at least), so they consider obsessing with something that is virtually impossible for the hope that it will happen a waste of time, of the finite life they have.
Then it boils down just to whether one is curious about it, or is curious about any other X subject.