I'd say its appropriate to call 'most/typical code' average code, not shit.
"Everyone is a shit driver" claims almost universally come from terrible drivers: When you have no situational awareness and aren't actively predicting the behaviors of drivers around you, and you don't have confident control of the tools at your disposal, every move that other drivers make seems dangerous and scary, needing panicked reactionary responses. Every trip is a perilous journey with tales of imminent death.
I honestly feel the same about people who walk around declaring all code shit. People who aren't competent with their development tools, can't naturally trace code and truly understand functionality, and can't adapt to different styles and era of code tend to be the ones, in my experience, that declare all code shit.