That's the official answer. The more nuanced and correct answer is that DOS (16-bit realmode) apps won't work due to the hardware lacking the functionality --- blame AMD, not Microsoft, for that --- but there's no such limitation for Win16 (16-bit protected mode) apps. Thus, WINE on a 64-bit Linux will handle 64, 32, and 16-bit Windows apps, and there's no emulation unlike with DOSbox and such:
https://www.dkia.at/en/node/180
(Coincidentally, I recently made a comment on another article about the nuanced nature of the word "supported": https://news.ycombinator.com/item?id=19578503 )
IMO they are making their life a lot harder by introducing all those frameworks and platforms every five years or so, but despite that they still make sure that stuff keeps working.
There are solutions, however.
For 16bit Windows software you can try https://github.com/otya128/winevdm which provides 16bit emulation and pass-through of Windows API calls to a mix of Wine and Win32 native calls. It isn't perfect but it can run a lot of Windows 3.x software. You can either drag-drop the executable on the emulator's exe file or use the supplied registry files to install it system-wide.
DOS software tends to work fine under DOSBox or vDos (a DOSBox fork explicitly made for text-based DOS applications).
Now i'm not saying you cannot find cases where stuff do not work, but in my experience most stuff work out of the box or with little tweaks.
