Possibly. Probably even.

High quality and consistent > Low quality and consistent > Variable quality and inconsistent. If you're going to be the cause of the regression into variable quality and inconsistent you'd better deliver on bringing it back up to high quality and consistent. That's a lot of work that most people aren't cut out for because it's usually not a technical change but a cultural change that's needed. How did a codebase get into the state of being below standards? How are you going to prevent that from happening again? You are unlikely to Pull Request your way out of that situation.