Poland is deeply corrupt, anybody working close to public sector know it very well. This is unfortunately all-European thing, when bureaucrats have too much to say, corruption is unavoidable. Democratically elected politicians are mostly foolish thus often unable to get away with a crime but also relatively poor (lack of any achievements before entering politics), so they are willing to take almost every single banknote offered.
to some extent arguably working against the interests of the state
...and this interest of state comes against interest of Polish taxpayers. Anyway this situation is quite funny, I read somewhere that if you wish to witness how PO realize their political program (lower taxes) you must bribe their leadership. :)
we should then be thankful to God we have such arrogant and at the same time ignorant politicians
So this is God the one who elected them? Should I thank you? :)
this shows something has to be done about these too - say serious embargos enforced
If you target bank secrecy to caught corrupt politicians, you also let the state to invigilate the rest of the society. This is not the way, the only way to reduce corruption is to reduce competences of bureaucratic apparatus.