Bad code is a problem. Like all such problems that accumulate over time, the causes are many, and the solutions can be painful. Nobody wants to spend money just to reduce technical debt, so chartering a project to refactor a code base can be a difficult sell[md]especially because the benefits are so hard to measure directly on the day after the refactoring project ends.
Just like getting into shape physically can prevent disease, putting your code on a "complexity diet" has long-term defect-prevention benefits that your company will appreciate. Leaving the "dragons" out there in the wild only tends to breed more dragons, more complexity, more expense, and more waste.