This is a good point - like most analogies, there are some places where the naked short argument fails. Certainly in small cases and/or known shortcomings - you can pay down in small increments. But how to handle things like the general gross architecture of system? That's clearly not quite the same.

As I see it, tech debt isn't enough of a descriptor of the kind of engineering shortfall one is experiencing. To understand precisely what one's talking about one needs to characterise the problem more.

My main problem is that the blanket term for the issue uses a best case analogy, when the worst case is so much worse; it's not funny.