Earlier quoted context omitted.
This doesn't make much sense. The counterfactual is that they'd be desperate to eat and take out a sky-high APR short-term loan. How is the new ability to take zero-interest loans "creating" the snowballing effect instead of reducing an already-existing one? This is called "the Copenhagen interpretation of ethics", in which any interaction with a situation in an attempt to improve it somehow gets warped into shoulder…
The payday loan puts backpressure on using it because it is obvious that the person is paying to use it. A zero interest loan does not communicate to the user that they are reducing their optionality until they are stuck.
Understanding that you've received X pesos now and will receive X less in two weeks is a lot simpler than implicitly calculating the NPV/default risk of high-interest loans, both from an intuitive and an explicit budgetary perspective.
Even if we (incorrectly imo) assume this dynamic plays out the way you say it does, it's quite a bold claim to say that this putative psychological effect comes close to outweighing a 3000% (or w/e) reduction in APR.