Earlier quoted context omitted.
3 years ago, in Cyprus, the reverse happened (savings were cut off) but people still deposit money into their bank accounts without getting increased interest, despite this precedent. Why should a loan writing off cause loan interests to go up?
Exactly because the situation is reversed: the banks are much more likely to be strategic and self preserving than the general public, due to concentration of power and many other factors.
In trying to apprehend reality as closely as feasible, it will not do to make assumptions like "all actors have constant (or even he same lognormal function describing) marginal utility" or "ignoring transaction costs and taxes."
This is most crucial in understanding behavior in vastly asymmetric situations (e.g. A Croatian making $100 a month vs a bank). Of course, much of our consumer tech industry is founded on this sort of asymmetry, so the concept is not out of reach; yet, we of the technical mindset often are too quick to use the lens of a convenient simplifying abstraction when it comes to political questions of economic incentives...