But it is much more a part of corruption to hold and manipulate debts than to release them. Debts are more often paid off by the wealthy and held over the poor as threats. So it decreases the power of the corrupt if history is not allowed to accumulate over time.
To limit the accumulation of debt, there was once a tradition in Jewish law to allow debts to only be held for so long, often 7 years, and for entire communities to release everyone's debts every 49 years and start over with a clean slate. Jesus is suggesting amplifying this, and not holding debts at all.
It is true that this lets abusers off the hook. But in the end, the momentary abuse is generally nothing compared to the leverage of accumulated manipulation that is the norm in our culture.
Also, you releasing your debtors is not a requirement for you to be forgiven. The word is 'as', in the same way, not 'as' in the sense of 'because'. It cannot be true that, as Jesus told the Apostles 'those you hold accountable, are held accountable' if those folks then get forgiven by forgiving others.
In a Catholic interpretation you get forgiven by the Law, or by the Church (who inherits that power granted by Jesus from the Apostles), and not by your own doing at all. In a more Calvinist interpretation it is not your place to judge, it is God's, and you have to forgive others just because you have no power or incentive not to do so. Your attempt at power is chasing an illusion, and it is your arrogance in presuming his right, not your vindictiveness itself, that God will punish if you judge others. There are intermediate positions that feel like you are forgiven because you are forgiving, but they are not very stable logically. (I am not really a Christian any more. So I am judging this by criteria an insider might not apply.)
Edit -- context:
That last fact makes it look silly that I answered the question. So I feel I need to defend myself against those who closed the first version...
I do have a context for interpreting Christianity in a way that is philosophical and not religious. I accept George Pixley's interpretation of Judaism as our oldest recorded attempt to build a large-scale fully-binding social contract not negotiated with a monarch or ruling family. (God eventually gave the Jews a king, but only several generations after the contract that limited his prerogatives was clear. That he then broke it twenty different ways does not matter, because it survived his dynasty anyway. No one else seems to have done that, in that order.)
Then Christianity is a more sophisticated philosophical revival of that basic proposition that allows for greater freedom and continuing revision on the basis of presumed, and not compelled cooperation with the process. Jesus's words matter because his motives are uniquely in tune with the original enterprise. And stable Christian sub-traditions are compelling to the degree they build interpretations of his words.