Here's why it doesn't sit well with pseudoconservatives (aka authoritarians):
It's consensual.
It involves giving accurate, scientifically based information to potential parents, on the risk of genetic disorders that might lead to unhealthy children, so that they can make better decisions about parenthood.
It does not involve racial pseudoscience, antisemitism, or violent compulsion of any sort. As such, it does not fit well with pseudoconservatism, fascism, etc.
They want it to eliminate phenotypes that are different...
Normal people want it to eliminate negative genotypes that lead to genetic issues and lifetimes of suffering for future generations.
Two completely different goals.
They just fundamentally don't understand genetics, like when you tell them there's more genetic diversity within Africa than between every other population outside of Africa. They can't see genes by looking at someone, but they can see phenotypes. So 9/10 a conservative will say "but they're all Black".
An astonishing amount of racism is actually about sex and reproduction. Many racists are more threatened by "race mixing" than by the mere existence of other races.
That’s not eugenics. To qualify as eugenics, you’d have to be getting genetic counseling because you wanted to improve the human race, not because you think it’d be unethical to make your kid go through the same suffering you did with a genetic disease. Making eugenics more palatable by ignoring the ideology that defines it can harm people, so please stop.
The end goal is to stop those diseases from continuing to affect the human race. Yes it starts with individual people but if we can prevent everyone from suffering, that is the goal. People need to understand that words are not bogeymen. Eugenics was used for horrible reasons by people who largely didn't understand the science, and by some who did. That doesn't mean it can't be used to accomplish something actually useful for humanity.