Counterpoint: Hayflick limit [1]. Of course, the humble lobster, jellyfish and hydra [2] (along with other animals) don't seem to undergo senescence but IMO the jury is still out on whether hominids are biologically amenable to such feats of genetic engineering.

The other question besides whether such a thing is possible is whether it is desirable. Depending on one's viewpoint, one could look at immortal humans as a cosmic cancer. At least the cycle of death and birth limits the harm a bad actor can do. What would you do if your least favorite fascist were also immortal and invulnerable? And I do mean that somewhat rhetorically. It's a messy ethical subject to think about, personally. I kinda prefer life and death.

[1] https://en.wikipedia.org/wiki/Hayflick_limit

[2] https://en.wikipedia.org/wiki/Biological_immortality#Organis...