Capitalism brought us children working in mines 6 days a week, company towns, and extreme poverty world wide.
Left-wing movements brought universal health care, lifted billions out of poverty with governmental spending on health and safety, and improved working conditions for billions throughout the world with regulations.
"righests" like the monarchists caused the famine in India that killed 30 million people. Fascists in Europe caused a war that killed 60 million people.
Authoritarian populist are always bad, regardless of their stripes. I don't know how/where you made up 150 million people starving, but right-wing populist are just as bad, and frequently worse than their left-wing populist counterparts.