If a developer writing in C/C++ is targeting Windows, then bringing in `<windows.h>` (and associated headers) is almost guaranteed, especially if said developer wants to work with native APIs (unless said program will rely on MinGW/Cygwin/Msys2, which are arguably worse, since they drag in an entire Linux directory tree per application).

This is just part of the cost of developing cross-platform, and I'm sorry, but to me, dismissing this as 'going out of one's way' is just being sloppy.

Are the developers of "Unix-first software (such as `ssh`)" targeting Windows though? I don't think so. They don't deserve to be shamed for this stuff. They aren't "sloppy", Windows is lucky to get ports at all.