Can you provide references? This is the first I’ve ever heard of this.
My point is not that the person I was replying to is definitely wrong about FDR's policies, but rather that the effects of FDR's policies are uncertain enough that the fact that FDR imposed them in the 1930s cannot credibly used to lend strong support to any argument for any economic policy to be imposed today. The post-WWII economic boom for example happened after most of FDR's policies had been repealed.