Junior dev: "Is it normal that the codebase is so difficult to work in?"
Senior dev: *stares into the void with thousand-yard gaze* "Years of tight deadlines, changing requirements, and revolving door of developers creates this beautiful disaster. Successful software either dies a hero or lives long enough to become legacy code that you'll maintain until retirement."
The brutal truth no CS degree prepares you for: technical debt is the REAL company debt. Your inheritance won't be wealth—it'll be 15-year-old spaghetti code with comments like "TODO: fix this before release" from 2009.