The Incas conquered and enslaved by Pizzaro didn’t practice human sacrifice, and were rather socialistic. Is there a connection? Socialism. It’ll stop you from barbecuing your kids to a pagan idol. Implement it in your country today.
The Incas did practice human sacrifice. Look up the death rituals for Huayna Capac. More than 3,000 were sacrificed in his honor. And they have been digging up frozen Inca sacrifices from the Andes for several decades. I don’t think you can talk about Socialism in what was a pre-industrial, basically Neolithic society, but I could be wrong. And Socialist societies in Eastern Europe and Russia had horrifically high rates of abortion.