There was evil in the world before capitalism and will be evil in the world without it. The root of evil isn't the economic system being used it's people who seek to control others. If Trump was voted in as a communist leader he'd be doing the exact same shit he's doing now.
I think the comment is the way fascism takes root is through greed and profiteering. If those traits/values weren’t rewarded they wouldn’t build power the same way.
While Capitalism might be relatively new in the history of humanity, greed isn't and and in many ways Capitalism can be argued to be just greed as a virtue.
Now greed, that in many ways has been described as the root of all evil. Yes, there are arguments about Pride being worse or more fundamental, but greed is persistent and eternal in how often it comes up.