That was to make the point very clear. Twh270 is correct. There's a whole spectrum of robustness. It's a constant fight to push towards the robust end no matter where you are on the spectrum.
The other big one I constantly fight have to fight for is using type annotations in Python. It's a total no brainer and definitely not an extreme end of the spectrum. I'm not advocating formal software verification.
It is abundantly clear that GP is roughly describing two ends of a spectrum, not enumerating every possible option.