Fwiw, though, I personally do use a ton of GNU software on any Mac I touch: coreutils, grep, sed, find, parallel, GCC, autotools, make, gdb, Emacs, and maybe some GNU Java stuff for LibreOffice, Bash. Most developers on macOS probably use at least a couple of those.
Because of the heavy push to GPL v3 by GNU, and because Apple’s interpretation of the license’s patent requirements prevented any GPL v3 code use, very few GNU projects remain as part of macOS.