I've read, on reddit and elsewhere, that corruption is really entrenched in the culture of modern Greece, from some stories of doctors only attending/prioritizing patients that bribe them, to politicians absolutely proven to be corrupt, but nothing being able to be done about them, or that the country could enter the EU after the country's economic numbers had been "cooked" by the government to appear to fulfill some requirements.

Opinions aside, all this is true, with the addition that Goldman Sachs was also involved in cooking the books (which doesn't really make the state any less corrupt). My opinion is that state corruption is being used by authoritarians as justification for punishing the Greek people with austerity measures, while they themselves don't work towards fixing the issue. For example, the troika causes a great deal of suffering to the lower classes using as a premise the big bad public sector is corrupt and therefore we need to fire all its workers and cut welfare and wages and privatize everything, the governments that created and accentuated this corrupt system and benefited from it also enforced destructive measures saying "we brought this on ourselves" as an excuse, while the idiots that kept voting them to power are attacking all alternatives in the political scene that try to improve the living conditions of this ravaged population by claiming that they ignore the root causes of the crisis and we should just continue doing what the troika instructs as to, ignoring that that strategy has failed (this subreddit is full of them btw). As soon as syriza came to power they committed to tackling corruption and, although every other government before that also made the same promise and didn't follow it up, they seem to be more serious about it, as they created for the first time a "Ministry against Corruption" and placed Panagiotis Nikoloudis, the most recognized Greek authority in dealing with corruption as its minister, despite him not being associated with the party before that. Time will tell if they do anything.