None of them has stood the test of time. Why though were they so influential in their day? Was it because Progressivism is so innately attractive a bundle of ideas that, like a potent narcotic, a few doses and the country was hooked? I think not.
The better line of historical analysis is to ask why Progressivism was so attractive to so many people in its originating era.
I think that Progressivism resonated with Americans as a political movement because it offered answers to problems that otherwise seemed insoluble. As Americans urbanized, they found that their teeming cities had a host of problems: crowded and dangerous tenements; a lack of clean water and sanitation; unhealthy drugs and adulterated food; alcoholism and opiate drugs; crooked politicians, law enforcement, and judges; rampant crime; corrupt business practices; and poor and exploitative working conditions in service to employers and industries that enjoyed great wealth.
The first generation of Progressivism identified these as problems and put forward solutions, often based on scientific and expert recommendations. There were building codes to assure safety and limit crowding; municipal water and sewer systems and waste disposal; restrictions on the serving of alcohol; new and higher taxes to finance public improvements and regulations to effectuate reforms; pure food and drug acts; anticorruption legislation; reforms like the direct election of US senators to get around the habitual corruption of state legislatures; and much else.
The opposition focused on constitutional arguments and had considerable success in court for many years. This in turn inspired anti-constitutional arguments and attitudes by later Progressives and an embrace of theories of history based on race and economic interests.
For some time, Teddy Roosevelt and Republican progressives coexisted in an uneasy truce with the conservative wing of the party. Sadly, Roosevelt and Taft split the GOP in 1912 and opened the way for Woodrow Wilson. That began the ascendancy of aggressive Leftist Progressivism.
This is a good point, and I would like others to see it. All of these works are, generically speaking, pretty horrible. And FWIW I don't think there's modern value in any of the works in that generic sense either. Where the value does lie is simply in the phrase "understanding the enemy". That is, progressives to this day still more often than not use the word "liberal" to cloak themselves even though they are routinely proud to admit, they hate liberalism. (This was brought up in discussion and its actually a crucial part of their evolution) Why are they still hiding? You know, why is that? What informs progressives of the inescapable need to hide behind the word "liberal"?
Ask many a progressive about John Locke and it will not take long for them to answer you while getting bent out of shape. Well why would that be? How could they possibly have negative opinions of Locke if they're liberals? It's because they're progressives, and only progressives. It's simple. Rush used to say a tiger is a tiger, a bear is a bear. Yeah, well, a progressive is a progressive. That's what they are. It's simple, very very simple.
As an aside, most of the remainder of your post I haven't quoted but I am in agreement with it. Progressives rely on what feels good to suck people in.
"Why though were they so influential in their day? Was it because Progressivism is so innately attractive a bundle of ideas that, like a potent narcotic, a few doses and the country was hooked? I think not."
I agree. When examined in depth, progressivism is profoundly ugly. But progressives have always, even from day one, possessed a keen understanding of the use of propaganda and packaging. So when they think everybody is with them and they run out and say "Administrative state!" everybody else is like "wait, what?" They run out there "Eugenics!" People again get confused, because the sales pitch and the more deeper message and especially the action/result just aren't matching. A doesn't stay A, it becomes an S and it's just bizarre.
It's why the progressive era is so important of a study. So, so important. The progressive era might very well be the most important era in U.S. history. The reason is though, it's not that the works have value because they stand the test of time on their own. It's so important because here comes Calvin Coolidge.
Coolidge whipped the progressives so thoroughly - after 1920 the progressives were so defeated and utterly humiliated and wiped out, that they were underground for over a decade and couldn't get out of it. Not until FDR came around and said "Hey guys, let's call ourselves liberals!"
Emulating Coolidge is the final act. But we can only have an idea how to do that, how to navigate the course, how to be Coolidge, how to become Coolidge, if we start with knowing and understanding Croly, Wilson, TR, Dewey, you mention Beard, but also Lippmann, Colonel House, Bernays, Creel, Hise, Goodnow, and a multitude of others.
The most important thing is this. It was the truth that killed progressivism. And it's the truth that can kill them again.
That's what we need.
That is why progressives hide.