In the early days when steel shot first showed up, the wads weren't as good as they are now. The introduction of the 3200 overlapped the development of steel on ducks and manufacturing ended in the early 1980s. Here's an article regarding the histories of the 32 and 3200. One of my lifelong hunting companions shoots his grandfather's four barrel set 32 that his dad inherited and he inherited from his dad. Simmons at one time made the subgauge barrels. It shows lots of use, but it keeps on ticking.

https://www.wildfowlmag.com/editorial/remembering-the-remington-3200/280104