As with any metaphor, technical debt has its' limits and its' traps. IMHO the biggest problem is that a comparison with lending implies that technical debt can be managed like people do with a loan. With loan you know how much of money-equivalence you take, how much you owe and how much interest you have accumulated on top.

Most of measurement - if at all possible - is much less obvious with technical debt. And inability to easily quantify it, opens up door for corruption.