BTW, when you say "Win32S" you mean "Win32". Win32S was a long-obsolete package to let 32-bit Windows apps run on 16-bit Windows if they didn't try to do too much.
Can't speak for today. At one point the S stood for Standard/Stable. That used to be a Culter-ism IIRC -- it was what was guaranteed to ISVs to be there. If you used anything else, Microsoft could (and did) pull the rug out from under you.
They added a bunch of new APIs and new stuff from 64 bits to et al. When Interix was done, all that they could guarantee was Cutler's interface.
I agree. However, I have spent much of my career on corporate Windows boxen, which are often locked down to prevent you from installing things, including WSL. Because Cygwin bypasses the regular Windows install system, it flies under the radar.
WSL should not have that problem these days for the exact reasons you mentioned, as you were correct that SFU/SUA did tend to be something that IT depts did not understand like (it was free but it was separate install). But WSL is just one of the standard options in Windows10 ever system can have it. You just have to enable it in the control panel and it will automatically do everything in a manner that should not be an issue to IT folks. Although it does require >>local<< admin privileges on the machines to enable.; IIRC.