Then, as now, too many uninformed people accept what the Dems say at face value without exploring the background behind the party--especially the people who contribute, mobilize for, and control the party's national leadership. For example, very few guys on the line who get the shop steward's voter guides understand how radicalized the leadership of their party--and their union--is.
Many people writing at FR are of the mistaken opinion that the Democrat party wasn't radicalized until late in the 60's. This is false. If you look at FDR's advisers, you will find a continuous thread between the Lefties, Socialists, Progressives, and fellow travelers of the 1930's and their children in the 1950's and 60's. One difference is that some (but not all) were anticommunists. The class warfare and identity politics of the Democrat party began seriously, though, with the New Deal.
One of the reasons the Dems are now talking about "talking about values" is that they realize just talking the talk is enough to keep literally millions of people on board. It has been doing so since 1932.
You're correct in saying that the party was pretty radical from at least the turn of the century onward, but they were better at concealing it then, and the rank-and-file did not share their views on communism and the like. I would say it is in the '60s that the "regular folks" started to wake up and see the Dems weren't for them.