> I don't know but it seems people (or at least old geezers) install GNU on top of Macs these days.

Me, I do this! I like being able to tack flags on after positional args if I remember them after typing a command. I like some of the convenience flags added to the GNU versions coreutils, grep, and findutils. Even `parallel` implementation I've used before is GNU parallel. I've never really learned mawk, to the extent I know awk at all, it's gawk.

(I don't like the common convention of prefixing them with `g` on macOS, either. I install them with Nix and just preempt the system ones on my PATH.)