Really, it's hard for anybody who knows anything about history to argue that it was economically effective. What we can still discuss, which I think is relevant now, is whether or not the real goals and the real effects of the policy was what it was sold as -- basically, an attempt to protect the poor at the expense of the rich.
I would argue that history has shown that this is rarely, if ever the case.
As an example, I'll point to Schechter Poultry Corp. v. United States.
First of all, for the millionth time "corporation" does not equal "rich".
The Schechter Brothers were Yiddish speaking chicken butchers in New York. Most of their customers were from the Jewish community who demanded Kosher meat.
Historically, for those who know about this case, it was clearly a story of the government wanting to test out a policy, in this case the NIRA, by targeting people that the state thought couldn't or wouldn't fight back.
The Schechters didn't speak English particularly well and they were a small operation. The inspectors weren't visiting the big companies every other day, they were visiting the Schechters. They were harassing the Schechters.
One of the regulations buried in the law in The New Deal that applied to the Schechters was a requirement of "straight killing" which prohibited, under federal law, the right of customers to choose their own chickens.
Now, seriously, I shit you not, this law prohibited customers from hand selecting and inspecting the chicken themselves before butchery; rather, the customer needed to place his hand in the coop and select the first chicken that came to his hand. That was federal fucking law.
Anyway, eventually the Schechters had enough and demanded that the inspectors leave. When they did, the Schechters were hit with sixty federal charges of which they were all eventually exonerated.
Now, one thing that the government specifically did to try and bury the Schechters was to place them between a rock and a hard place. Namely, the Schechters needed to admit to violating the straight killing law and risk prison; or, they would need to deny the violation which would destroy their business because they'd have to admit to their customers that they lied and sold them a product that they didn't select. They decided to risk jail and that lead to the SCOTUS striking down much of the NIRA.
To rush to the end of this, this whole packaged deal that was sold to the public as being for the poor actually was weaponized against the average citizen rather than the ultra-rich. This isn't an exception, it's the rule. You should never believe the government when they claim that a policy will target the rich and not you.