And how would we know which mutations are broadly beneficial or not? What if humans of a future earth or larger society have needs we couldn't imagine, like radiation resistance or anti-autoimmune protections?
Besides, sometimes there are trade offs with no clear winning picture. Sub-Saharan Africans with sickle cell syndrome are also more resistant to malaria. What's worse? What's more necessary? How do we know malaria won't be a bigger problem tomorrow?
>how would we know which mutations are broadly beneficial or not?
In general terms we know what a good specimen looks like and the specific traits that they have. We can only build to that because:
>sickle cell syndrome are also more resistant to malaria
This is evolution by process of elimination, and unfortunetaly elimination means lack of breeding from disadvantaged phenotypes. We've largely uncoupled reproduction from evolutionary advantages anyway, and just like humans are so dedicated to controlling the world in they inhabit, we'll insist on controlling the finest details of reproduction too.
Besides, sometimes there are trade offs with no clear winning picture. Sub-Saharan Africans with sickle cell syndrome are also more resistant to malaria. What's worse? What's more necessary? How do we know malaria won't be a bigger problem tomorrow?