I can think of little modern philosophy more regressive than the idea that a self-appointed superior can determine that another is inferior to the point that they (or their offspring) should be culled from existence. Eugenics and racism have been intertwined since the beginning and with a modern twist continue to target vulnerable populations.
This is why thought experiments like the Trolley problems don't have a simple answer.. and they get even more complex with variations of the thought experiment.
However, please tell me which model of ethics supports eugenics. Is it Utilitarian, Rights, Fairness, Common Good, or Virtue?