You're not dealing with the geniuses. You're likely just dealing with people smarter than you. I can assure you geniuses are rare, and people of the same intelligence level tend to gather so you can go through a career completely missing them depending on where you work. There's enough noise such that among these groups you won't notice the correlation.

Tbh the geniuses don't view their own code as shitty, to them it's quality. It's only viewed as shitty externally.