USA's New Deal: potentially millions saved from starvation.
That's the problem with those comparisons: it's easy to point at the precise body count of radical experiments that went the wrong way, but quite hard to enumerate the lives saved due to those that worked out. Kind of survivorship bias in reverse.
I'd guess the establishment and enforcement of sanitary standards (which, at the beginning, was considered quite radical) saved more people than all dictators of the world together managed to kill. But that's as hand-wavy as anything else in this subthread.
