There are major bioethical objections to surrogacy.
There's no agreement about what factors to consider. Alabama guidelines would exclude patients with severe mental retardation. New York policy is to maximize the number of lives saved—meaning a 90-year-old patient would get the same priority as a 20-year-old.
There are virtually no regulations for CRISPR technology.
Pediatric oncologists must sometimes call in authorities, or ask themselves whether the care they're providing is doing more harm than good.
If there is limited or no psychological continuity, the original person won't benefit: They are now truly dead, since their body and brain have become a new person.