If Pauling's eugenics policies were bad, then the laws against incest that are currently on the books in many states (which are also eugenics policies that use the same mechanism) are also bad. There are different forms of eugenics policies, and Pauling's proposal to restrict the mating choices of people carrying certain recessive genes so their children don't suffer is ethically different from Hitler exterminating people with certain genes and also ethically different from other governments sterilizing people with certain genes. He later supported voluntary abortion with genetic testing, which is now standard practice in the US today, though no longer in a few states with ethically questionable laws restricting abortion. This again is ethically different from forced abortion.
FWIW my understanding is that the policies against incest you mention actually have much less to do with controlling genetic reproduction and are more directed at combating familial rape/grooming/etc.
Not a fun thing to discuss, but apparently a significant issue, which I guess should be unsurprising given some of the laws allowing underage marriage if the family signs off.
Mentioning only to draw attention to the fact that theoretical policy is often undeniable in a vacuum, but runs aground when faced with real world conditions.
This is mentioned in my link: "According to Pauling, carriers should have an obvious mark, (i.e. a tattoo on the forehead) denoting their disease, which would allow carriers to identify others with the same affliction and avoid marrying them."
The goal wasn't to mark people for ostracism but to make it easier for people carrying these genes to find mates that won't result in suffering for their offspring.
https://scarc.library.oregonstate.edu/coll/pauling/blood/nar...