Flying blind
The “self-exclusion” by debtors who are formally entitled to support but refuse it so that the protection of the privacy of their banking transactions will not be lifted is a serious indication that the state is in no position to properly plan any social support policies.
The reason is simple: It cannot calculate the real number of true beneficiaries because it has no picture of the real state of their finances.
This is a serious failing that exposes the breadth and depth of the antisocial consequences of tax evasion.