Very interesting in-depth post! I would like to share some thoughts regarding your post if that's ok:

Thanks, michelmake! Any thoughts and criticism are welcome.

Regarding the high number of students pursuing higher degrees (you mention 40%). You are mentioning that this number is much higher than most other European countries. I am guessing that this might simply be attributed to the lack of job opportunities for graduate students in Greece.

Well, I didn’t say it’s much higher. You can see some of the relevant statistics here, but the figure is indeed around 40%. I don’t know how much higher that is compared to the EU average, but it shouldn't significantly change any of my conclusions, since it's a broad-stroke analysis. But I suppose you’re right: Any difference might be driven by the limited job opportunities in Greece.

As a matter of fact, as a Ph.D. student working in Germany (I'm Dutch myself), I've met quite a large number of Greek students that are pursuing a second, or even third masters degree abroad, simply because there is a lack of well paid jobs in their home country.

That’s true. However, only a small fraction of Greeks pursue a Master’s or Doctorate (either in Greece or abroad). Most either don’t have the skills, or they lack the necessary capital. It’s mostly smart students with multiple nationalities and/or well-off parents that can do it. From my own experience, I’d say only between 10 and 20% of Greek students fall into the category you’ve encountered. This is supported by several Greek university department evaluations, such as this one.

Interestingly enough, the aforementioned percentage happens to more-or-less coincide with the fraction of people with an IQ that’s at least 1 sigma above the mean. In hindsight I don’t think that’s really surprising, given how tightly IQ correlates with things like education level, income, and job performance. But of course it’s taboo to talk about human intelligence.

A good amount of these Greek students I've met are not planning to go back to Greece anytime soon. Typically their first choice is to find a job abroad with a good salary and other benefits. I think this is where a lot of potential is lost for Greece itself.

Ah yes, the infamous brain drain. I happen to belong to the same category of people, and I share the same sentiments for the reasons you mentioned. There’s two more personal reasons I’d like to add: political instability and outdated social structure. The 80–90% that stay behind are the perpetual students, which have to be eliminated. They’re worse than a brain drain in the short term, plus their effect is rather easily quantifiable.

First, the Greek government invests in their students' bachelor degree, followed by a large number of these student leaving the country due to the lack of jobs and study abroad opportunities. As a result, the invested government money is flowing away into foreign economies by a drain of human capital into other countries.

I’m fully with you on this one: Brain drains suck for the economy, for the reason you mentioned. However, the capital lost by a brain drain is harder to estimate and is only felt at least half a decade later (when students finish their studies and start a job abroad). It seems to me that dealing with perpetual students is easier than preventing bright students from leaving.

I hope I adequately covered most of your points, and would love to hear any further thoughts you might have on the subject.