I'm fine with the contempt approach. New business priority comes in, and the software can't support it because of tech debt, so someone fixes it.

Otherwise, even if people tackle the tech debt in good faith, they spend endless time polishing things that don't really matter. Something big like a database or API is deeply flawed, and they focus on improving the unit tests, which further entrenches the broken stuff because any replacement now has to meet the same standards.