Eugenics was a tactic to rationalize white supremacy, a desperate conservative attempt to resist the progress of abolition & integration. Prohibition was an ultra conservative, (mostly) religiously motivated movement trying to impose an archaic sense of morals on the country and fight the evolution of how people chose to spend their free time.
Change can go in either direction -- it makes absolutely no sense to lump all change under the umbrella of progressivism.
"Progress" refers to things like the 13th amendment, the 19th amendment, the Voting Rights Act of 1965. Obviously. Progressivism is about change that advances human rights.
Conservatism is about asserting moral superiority, even at the expense of human rights. Eugenics and prohibition are prime examples of conservatives trying to cut the legs off of progress.
The Roe v. Wade ruling was another progressive change. It was a victory for women's rights. Texas now re-imposing bans on abortion is a conservative change.
Any other time & place, moving in the opposite direction of progress would be considered "regressive".... Only in politics can we call it "conservative"