It would be a so-so argument if it was true. (It is not) How DNA is expressed is a part of the story as well which involves many environmental factors both in utero and after birth.

We do not totally understand how it works, but there are heritable traits not passed via DNA - the one often in the news is women with emotional trauma pass that trauma on to their children, and those children show those symptoms even if raised in a happy home with 0 contact with the mother.

It is a philosophical argument, not a scientific one. One which if we try and reason based on how special nature treats embryos quickly falls apart anyways...