Well, Cygwin and Busybox have shown me that fork-heavy activities are about 100x slower on Windows than Linux.

The Windows approach may be correct, but it suffers in performance from the POSIX perspective.

I have heard that WSL1 iimproves this.

Linux has worked pretty hard to optimize fork(). This doesn’t mean that fork() is a good idea.

Windows does not historically depend on fork(), so there was no native fork(), so Cygwin kludged it up.

	▲	JdeBP 42 minutes ago \| parent [-]
		Actually, there is a native fork. There had to be, as POSIX personality support was a part of the Windows NT 3.1 design. What there wasn't was a Win32 form of fork. The Native API for Windows NT allowed it quite straightforwardly.