I struggled with this. I didn't have the guts to not use "tech debt" in the title and throughout the book. I wanted to coin a new term, but didn't find anything that worked.

There are parts of the debt analogy that (I think) really hurt getting it dealt with. I think that explaining it like that to non-engineering decision makers will make them think they understand it and then quash projects based on some kind of ROI analysis of debt payments. They'll be happy to have the debt.