That's due to a lack of theory and useful abstractions in the tools used to modify genes. We're so early on in the development of that field that if this were c

That's due to a lack of theory and useful abstractions in the tools used to modify genes. We're so early on in the development of that field that if this were computers, we'd still be assembling devices by arranging logic gates by hand. Custom cosmetic gene therapy is a great way to incentivize the better tools.