There's a bit of nuance in what I was saying.... I agree (and agreed) that Windows 3.1 didn't include Win32s. What it _did_ include, though, is direct support for Win32s in the form of PE executable detection and a hook for the (separately installable) Win32s PE loader.
I deployed and supported 3.0, 3.1, WfWg 3.1, WfWg 3.11 and Win 3.11.
AFAICR after some 30y, none of them included Win32S as standard.
And no, I don't recall any earlier 32-bit binary or API support.
I think there were some dozen versions; 10 are listed here: https://www.classicdosgames.com/utilities/win9x.html
... and that does not include 1.0.