Why are eugenics considered "pseudo science" when it's quite literally just applied genetics?

We're even doing it right now in most western countries anyway.
The sperm of attractive and successful white men is sold for many thousands of dollars, because despite how uncomfortable it makes some people, everyone acknowledges on some level that some people just have better genes than others.
Not to mention that the majority of western women choose to abort heavily defective children, one's afflicted with down syndrome for example.
That is literally just eugenics as well.