Although I've made this joke myself in the past, about tax evasion being our national sport, it's insulting to see it repeated by an Australian publisher. Personally, I've only had to pay taxes abroad, in the UK, where there was no opportunity to evade them (because they were directly deducted from my salary - I'm a PhD student now hence the past tense). I wouldn't really say I'm an expert tax evader.
That said, any discussion of taxation and tax avoidance in Greece as well as the rest of South-Eastern Europe must also take into account the sorry state of public services, which tax money is meant to support. It's a chicken-and-egg problem, but it's easy to see why nobody would want to be the malakas who pays their taxes properly only for their tax money to disappear down the black hole of corruption before having any chance to improve the national health service, education, our roads, etc etc. Taxation makes sense when it's spent to improve and maintain the commons - not to line politicians' pockets.
Of course, that's not absolving my fellow Greeks of responsibility. Corruption is high in Greece because we support corrupt politicians with our votes, and because we have done so for three generations since the "metapolitefsis", the change to democracy after the years of the military dictatorship (ended in 1974). To wit, Kyriakos Mitsotakis (the current prime minister, pictured in the article) is the second Mitsotakis to be prime minister, grandson of the first - and his mom is also an MP. And before him we had Papandreou I (in the '50s), II and III and also Karamanlis I and II to rule us (and all their friends and cousins as MPs). We keep voting the same "houses" in power and then complain that they suck us dry and destroy the economy. And then of course it's every man and woman for themselves.
It's a fucked up situation and we are very much guilty for our choices over the years. But silly jokes about national sports don't help to get to the heart of the issue, or convey its seriousness.